[FEATURE] Refactor category tree to SVG

Replace ExtJS category tree implementation with SVG based one.

Current approach reuses as much of the category logic as possible
(e.g. ExtJsJsonTreeRenderer)

The SVG tree js component is added as requirejs module.
Standalone version of the js component lives here:
https://github.com/wmdbsystems/TYPO3.Tree

Done:
- virtual scrolling (we render only the number of nodes
  which fits the current viewport) so there are minor workarounds in place
- displaying of the category tree in category record (including checked checkbox)
- a new ajax controller is added which returns full tree as json
- icons are displayed
- searching/filtering through tree
- collapse all and expand all buttons
- toolbar (search, expand all, collapse all)
- indeterminate state for checkboxes (parent is marked if child is selected)
- selection saving in the record
- maxItems handling
- new svgTree is used in all records (pages, tt_content, categories, ...)
- TCA settings: 'expandAll', 'showHeader', 'size', 'maxLevels'
  'nonSelectableLevels', 'requestUpdate', 'exclusiveKeys'
- toolbar tooltips and input placehoder
- replace collapse-all and expand-all icons with new ones from T3.icons
- remove extjs JS file (tree.js)
- readonly mode (it's possible to navigate the tree (scroll,collapse,expand,etc),
 before it was not possible)
- marking record “red” if validation fails
- icon overlay handling (for e.g. disabled categories)
- tooltip with category id

Resolves: #76108
Resolves: #74126
Resolves: #65780
Releases: master
Change-Id: Ib8d3c879b0b0584ff50cf0f6842bb655f9753ddd
Reviewed-on: https://review.typo3.org/48060


Tested-by: Bamboo TYPO3com <info@typo3.com>
Reviewed-by: Benni Mack <benni@typo3.org>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Georg Ringer <georg.ringer@gmail.com>