Removes Raphaël 2.1.0 library.
Removes Raphaël mentions from timelines.

This also adds a soon-to-be drop-in replacement for Raphaël paper in the
form of a SvgHelper Angular facrory.
SvgHelper interface improvements.

Adds most methods expected from timelines' Raphaël usage. Also adds
SvgTextHelper.
Adds more SVG helpers.

Adds/improves wrappers for text and rect elements in SVG.
Removes intermediate helpers.

Adds methods directly to the DOM element prototypes.
Merge branch 'feature/ui-component-timelines' into feature/ui-component-timelines-without-raphael

Conflicts:
	app/assets/javascripts/angular/directives/timeline-table-container-directive.js
Reveal timeline after loading is complete
Remove raphael from manifest
Update svg helper
Fix typo


(see 2d1ee)
Fix background rectangle positions


(see 39fc0)
Ignore expansion state of root if there's a subproject in timelines
Move stuff from timelines controller to timeline container directive
Freeze gon to version 4.0.0


As a work around gon is included via the timelines helper where later gon version lack the local env variable
Merge branch 'feature/ui-component-timelines' of github.com:opf/openproject into feature/ui-component-timelines