jsdoc - PIXI documentation filtering

Added the filterpixi.js jsdoc plugin which marks some PIXI
interaction-related methods and properties as private. This ensures that
they do not show up in the final Phaser documentation.
jsdoc - added namealias

The namealias plugin gets jsdoc to detect lots of documentation it was not
correctly picking up due to the application of the `name` property. This
can be read about in
https://github.com/jsdoc3/jsdoc/issues/804#event-195287680 - this results
in _much_ more complete documentation generation, especially when
properties are defined in constructors.
jsdoc - short/friendly @link plugin

Added support for short `{@link #member}` markup. This makes interlinking
much cleaner and shorter; similar short-link support was available in
previous versions of jsdoc.
jsdoc - sourceproxy docs and cleanup
jsdoc - namealias fix

Fixed issue with namealias and class doclects without names.
Merge pull request #1385 from pnstickne/wip-jsdoc-core2

jsdoc core/plugins