* addChild/removeChild transform IDs were wrong

* better test

* uncomment expects

* also add removeChildren

* lint on tests

* Add missing 'flag updating'

When add or remove child , the flags should be changed.

* Update Container.js

* Update Container.js

In some complex use case ， users would call updateTransform manually.

And , if  `renderWebGL` is public , `updateTransform` should be public too.

Class member documentation improved via removal of unnecessary @memberofs - more members now show up in the docs.
Class getter/setter documentation improved using technique above, and also by removing documentation for setters. Documentation was only showing the setter docs, whereas the getter is where the important information is. JSDoc maintainers themselves recommend just doccing the getter jsdoc3/jsdoc#973
Documented a few classes to let devs know that they are automatically created by PIXI and added to renderer.plugins, like interactionManager and prepare

* Improved documentation of the destroy method
Documents the .texture and .baseTexture parameters for the settings object that may not be used for the class itself, but could get propogated down to children
Fixes https://github.com/pixijs/pixi.js/issues/3407

* Improved clarity of docs

Also tweaked container to use renderer.flush instead of starting /
stopping objectRenderer.

no new arrays being created here! Also tweaked the eslintsrc to   allow
us to not have to use rest.

Index can be 0

* added prefer-const rule to .eslintrc

* eslint const autofixes

* manual let to const changes; lint free;

* added brace style 'allman' to eslintrc

* brace style, comment fixes and default arg

* brace style fixes

* more brace styles

* Point default args

* Point brace styles

* Observable Point default args

* more brace styles

* jsdoc comment style

* brace style

* brace styles and small jsdoc fix

* brace styles

* removed unneeded eslint inline comment

* brace styles; lint free