Overlay sources.
TODO updates.
Fix for dead RegExprs in stylesheet literals vivified from localstorage.
Quantitative track scales in SVG export.
Propogate feature hierarchy to listeners and popup code.
Fixed glyph-lookup for empty space within groups.
(Mostly) fix double-click behaviour.
Stop GridGlyphs grabbing clicks.
Per-tier featureInfoPlugins.
added Ensembl REST API example to test.html
Fixed e!transcripts mapping.
Be careful about when in the request cycle we set XHR.responseType, so as not to upset Firefox.
Fix for situation when click on popup close button filters through to underlying canvas.
TODO changes
Propogate source capabilties through overlay system
Merge branch 'master' of github.com:dasmoth/dalliance
Updated Dalliance code