Merge branch 'dev' into dev-v4.0.0 ...

# Conflicts:
#	bin/pixi.js
#	bin/pixi.js.map
#	bin/pixi.min.js
#	bin/pixi.min.js.map
#	package.json
#	src/core/index.js
#	src/core/renderers/webgl/WebGLRenderer.js
#	src/core/sprites/Sprite.js
#	src/core/textures/Texture.js
#	src/core/textures/TextureUvs.js
#	src/loaders/spritesheetParser.js

removed debug so source map is not bundled in to js

filter stuff working better

Add informative header, fixes #1873

fix #1946; ensure exclude is an array

Minifying now adds source map comment ...

The sourceMappingURL comment is needed to use the JS source map

Remove dead karma config

Cleanup, remove references to old files PolyK SpineRuntime

update jsdoc config for jaguar

proper use of gulp task and updated readme ...

link to the new template repo

fix slow dev builds

working on #1713, use standlone for export

fix bundle ignore

merge #1575

remove browserify standalone and manually export; fixes #1574

Upgrade browserify, and use karma-browserify and karma-chai

Merge pull request #1554 from drkibitz/feature/docs ...

Feature/docs

change karma path to pixi build ...

gulp build pixi to bin/pixi.js

exclude polyfills from docs

ignore third-party scripts in jsdoc

Use gulp-sourcemaps and write maps for both debug and release

write sourcemap to separate file

change jsdoc task to run npm script

export pixi.js for other bundles to require

update jsdoc to go through all src

fix #1283; allow exclusion of modules

fix bundle on watch update

fix watch tsk

fix some require paths that changed with some refactoring

remove isDev; always output sourcemap; add uglify