Change range content to overflow nicely if the range width is smaller
than the width of the text. This prevents range items with longer text
lines from being completely hidden.
Also update the stacking collision check to handle this case so that the
overflowed text is not hidden by another item.
Added drawing with schematic overview of vis.js
Graph now uses an id based set of nodes and edges instead of a row based array internally, and supports DataSet
Fixes and improvements in DOT parser regarding subgraphs
Graph is robust now against edges connected to non existing nodes
History updated
Improved hiding non visible items in Timeline
Implemented grouping support in the Timeline
Fixed selection of nodes in the Graph when the page is scrolled down
Merge branch 'master' into develop

Conflicts:
	src/timeline/component/css/item.css
	vis.js
	vis.min.js