Small fixes and tweaks for v5 (#5329)

Sprite, Mesh and Graphics refactor to including in batching, Take 2 (#5132)

Revert "[next] Sprite, Mesh and Graphics refactor to including in batching (#5069)" (#5127) ...

This reverts commit 4743491.

[next] Sprite, Mesh and Graphics refactor to including in batching (#5069)

Add caching of geometry signature to limit VAOs (#4837)

Pedantic spelling fixes (#4797)

Adds a caching layer to generateSyncUniforms (#4792)

Replaces PREFER_WEBGL_2 and options.legacy with ENV and PREFER_ENV (#4718)

Reorganize the core module to be flatter, rename WebGLSystem to System (#4707)

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

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..

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

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 getTestContext, getBufferType and interleaveTypedArrays from utils (#4396)

Next Restructure for v5 (#4387) ...

* Reorganized files

* Adds new files

* Adds new files

* Updated to next-lerna

* Linting fixes, disable deprecations

* Created bundles and plugins folders

* Adds polyfill plugin

* Test pass

* Better build dest selection

* Externalized fragment shaders and vertex shaders

* Renamed plugins to packages

* Creates core package, updates Rollup version

* Reorganized pixi.js into packages

* Added packages, readmes, licenses for all packages

* Resolve minor build, dependency issues

* Ignore non-first comments with uglify

* Fixes fragment dependencies

* Adds settings, constants, utils, math, display, app

* Fixes import issues with core

* Fixes build all modules, updates deprecations

* Fixes listing issues

* Temporarily disable coverage

* Broke up tests

* Rename GeometryBuffer to Buffer

* Fixes tests for all

* Remove placeholder test

* Adds test for constants

* Add test for accessibility

* Created integrations tests

* Travis-friendly test concurrency

* Un-did concurrency for tests

* Better tester shebang

* Temporarily disable tests for mesh

* Log out floss error

* Moves filters to new filters root folder

* Combines premultiply, deprecates PIXI.extras namespace

* Documentation fixes

* Moves integration tests to tools

* TimeLimiter test is too unstable for slow environments