Merge branch 'dev' into dev-geometry-update ...

# Conflicts:
#	src/mesh/Mesh.js

Remove the needless checking for `orig` (#3479) ...

In Texture , the `orig` is always exist after new Texture object . 

 If `orig` is not accessible , there will be a bug in the App.
The developers must fix it , not ignore and return `0`.

fixed settings not being respected (#3315) ...

Discovered that using this kind of code:

```const { MY_SETTING } from settings;```

means that changing settings properties has no effect as the objects
are being set before the user changes them.

Moves constants that are actually settings (#3298) ...

* Made const that are setting writable

* Moved more items to the settings

spelling

Dev texture states cacheing (#3201) ...

* minimal texture bounds pass 1

* cheeky opts

* tidy up code

* create empty textures

* added empty texture

* couple more tweaks

* fixed empty texture issue

* fixed tweaked so id's sit on glTexture

means it should work on multiple contexts

* tweaked unbound textures

* tidy up

* upped max textures to 4 for mobile!

also sending state to tiling sprite VAO

* removed _activeTetureLocation

* tweaked eslint

* make sure buffer is bound

* updates based on @englercj review points

- Added vertexCount back in as it still yields much faster results in
iOS
- Tidied old comments
- Replaced i++ with ++i

fixes #3159

use objects where we map render context ids

add HTMLImageElement check to fix #3099

Revert "Revert "Fixes Texture.from variable error"" (#3103)

Revert "Fixes Texture.from variable error" (#3102)

Fixes #3100

clear lint warning

Update docs: issue #3085 ...

#3090: Putting this out here. After encountering #3085 this is what I found. Please feel free to revise as needed, as I admit my knowledge on the matter is limited. I hope it helps someone else.

Merge pull request #3060 from englercj/fix-image-url-detect ...

Replace url extension regex

remove some changes from texture

1. moved clamping into TextureTransform ...

2. texture now has an optional component

some restructuring

Clamping is magic

clamping is hilarious ...

THIS IS THE PAIN

Giant tilingSprite refactoring. ...

1. Rotated and trimmed textures are allowed
2. "full" textures use simple shader if they have WRAP_MODE.REPEAT
3. WRAP_MODE.REPEAT is forced if that texture uploads in TilingSprite first time
4. TilingSprite now has tileTransform which applies to the "zero tile" like if its been a child

replace url extension regex; fixes #3059

VideoBaseTexture fixes and changes ...

* https://github.com/pixijs/pixi.js/commit/8d39e810c595b0afc48e542b2d4cad9c204cc7d2 didn't fully solve the video loading issues; the examples page for videos still doesn't work. I've tracked that down to the static 'fromUrl' function, which called video.play(). This was a tad early, resulting in width and height being 0. Removing the .play here doesn't matter, as it is still automatically called within _onCanPlay()
* autoUpdate changed to a getter/setter. It's previous doc stated that it could be used to control when autoUpdating happened, but this wasn't true, it was actually just an internal variable to check whether it was currently auto updating or not. I've create a couple of private tracking variable for the state, whilst the public getter / setting now truely controls autoUpdating and can be changed on the fly.
* moved this class to use the ticker. My expectation as a dev is that if I stop the shared ticker, PIXI would stop, but VideoBaseTexture was an exception as it used rAF directly.

Fix some loading issues; fixes #2687

Merge pull request #3024 from englercj/export-default-cleanup ...

cleanup some export defaults

clean up to be specific

cleanup some export defaults

Huge refactor to match a new shiny eslint file.

Fix issue when creating a BaseTexture with a 'null' source value, then using .loadSource() with an already-loaded IMG element. The 'loaded' event is never fired in that case and Texture objects are forever waiting for the 'loaded' event to be emitted

Better SVG support (#2614) ...

* Better SVG support

* Images are loaded using canvas which enables pre-scaled textures
* Scaling is done by providing an extra parameter `sourceScale` to the `fromImage` method
* Size of the original SVG source is checked with an extra XHR (necessary step for the canvas API to work)
* Supports data URI based SVG

* Fixed brace-style.

* Added util tests.

* Rebased to latest dev. Added 'px' support.