* 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..