First pass at tidying up shader (#4688) ...

* First pass at tidying up shader

- reduced GLShader to be a storage object
- also GLShader renamed to GLProgram as it is attached to programs
- This above two points bring it in line with GLTexture and GLBuffer
- Now shader inspection only happens once instead of twice!
- Removed unused classes
- moved precision check to program

* Fixes linting

* tidy up of GLProgram

* Set type to be object

Fixed up resolution issue with RenderTexture (#4695)

Feature/filters (#4687) ...

* Done
- filters working
- nested filters working
- Less GPU calls than v4
- Now passing destination and source frames to shader to calculate verbs
- ONLY Color Matrix Filter working
- Filter Area is now transformed (like hit area, much more useful!)
- Less code :D

Todo
- Apply Filter no complete
- Multiple filters not. Complete
- Refactor other filters

Optimisations
- need to pool the FilterStates

* Smarter check to eliminate needles enabling of stencil

* - Quad draws with triangle strip
- multiple filters now working

* Fixed up resolution

Not only does resolution now work - but any texture pass can be ANY
resolution and it works like a champ!

* Moved docs removed a needless comment

* More optimisations

- Added caching layer to viewport
- renamed getRenderTarget -> getFilterTexture
- added active state to filter for easy access
- fixed and optimised blur filter at least 66% less gpu calls required
now :)

* Fix up alpha filter

* Fixed up all bundled filters!

* Filter clamp added to Displacement filter

* Fixed lint fail

* Fixed up use of ba instead of zw in shader

Also added defaultFilter vert

* Added doc to state in filter

* space..

* Added pooling and a few docs bits

* more tweaks

fixed blur Y filter bug
Fixed default filter frag bug
Set default padding to 0

* Removed the slice from filters #3639

* Added auto fit back in

We now Loop through filters to find appropriate padding / autoFit /
resolution rather than just checking first filter.

Also clamped blur in vertex shader so that it does not bleed
transparency around its edges

* Update eslint package

this seemed to fix it last time..

Expose earcut dependency in PIXI.utils (#4676)

[next] Particles fix (#4600)

Fixes Garbage Collector system (#4593)

[next] Math `copy` inconsistencies (#4595) ...

* copy-from and copy-to inconsistency

* faster copyFrom for ObservablePoint

* deprecations

* Fixes deprecations docs

Windows tests are failing (#4589)

Update LICENSE files to 2018 (#4585)

Bugfix/frame buffer textures (#4578) ...

* Fixes issue with frame buffers if depthTexture or colour texture are auto generated

Easy fix, we forgot to update the texture constructors to use the new
resource / object format.

* Lint fix, oops

Fixing mipmaps and renderTexture (#4559)

Removal of pixi-gl-core dependency and refactor of GLTexture (#4547)

Cleans up documentation to remove JSDoc globals (#4542)

shader's source when check precision (#4510)

Texture and Resources Refactor (v5) (#4507)

Fixes NodeJS APIs (#4498) ...

Fixes NodeJS APIs (v5)

Region parameter for Renderer.generateTexture() (#4477)

Refactors bundles exports, more consistent generation of bundles (v5) (#4475) ...

* Refactors bundles exports, more consistent generation of bundles

* Incorrect trailing comma

* Cleanup getting package JSON fields

* Alphabetized the list of imports and exports

Test and build system optimizations (v5) (#4460) ...

* Adds optimizations for test and build system

* Fixes cannot pass undefined to describe

* Support multiple build outputs

* Removes builder and tester internal packages

* Removes unnecessary package.json file

* Bumped buble version, sorts package.json deps

* Fixes dist command for deploying bundles

Extract fix (v5) (#4437) ...

* Fixes extract for v5

* Add catch for an empty container

* Fixes linting issues

* Tweak extract function

Decouple Canvas Functionality (v5) (#4429) ...

* Create canvas-renderer package

* Externalized all canvas-related functionality as packages

* Creates pixi-modern package (no canvas)
* Renames PIXI.WebGLRenderer to PIXI.Renderer
* Removes “WebGL” from class names, makes default

* Include modern build to Travis deploy

* Fixes linting issue

* Fixes app test on Travis

* Fixes Travis issues with app-loader mixin

* Add missing CanvasRenderer from accessibility tests

* More de-coupling, using _renderCanvas mixins, pixi.js inherits pixi-modern

* Re-adds missing dependency

* Re-adds other missing dependencies

* More strict comments elimination

* pixi-modern as a dependency is slow and bloated, undoing

* Fix ES global object

* Moves pixi.js to pixi.js-legacy

* Move pixi-modern to pixi.js

* Shared deprecations between bundles

* Adds unit tests for window

* Reorganized canvas and filter packages

* Renames renderWebGL functions to render

* Creates new canvas-display package for last of canvas functionality

# Conflicts:
#	bundles/pixi.js/src/index.js

* Removes preprocess, better deployment

* Removes deprecation packages, pixi.js-legacy now inherits pixi.js

Removes PIXI.ticker Namespace (v5) (#4413) ...

* Removes PIXI.ticker namespace object

* Fixes documentation

fixing destroy() (#4423)

Fixes issues with build process (#4415) ...

* Fixes issues with build process

* Documentation cleanup/fixes

* Removes empty rollup config files, ES6 builder code, deprecations to builder

Improved Deprecation Strategy: Take 2 (#4410) ...

* Better deprecation strategy with bundle

* Fixes listing issues

* Optimization for Build Times with Rollup (#4411)

* Single build for both ES and CJS/UMD formats
* Simpler bundle mode
* rollup-watch is deprecated

Removes pluginTarget from utils (#4394)

Removes URL_FILE_EXTENSION and getUrlFileExtension (#4397) ...

* Removes URL_FILE_EXTENSION and getUrlFileExtension

* Inline file extension inspection from v4 for createResource

* Move extensions into resources

Moves SVG_SIZE and getSvgSize, and docs resources (#4395) ...

* Moves SVG_SIZE and getSvgSize, and docs resources

* Moved SVG util tests to core

Removes getTestContext, getBufferType and interleaveTypedArrays from utils (#4396)

Document caching behavior of BaseTexture.from (#4390)