Quick Outline setup
Merge branch 'master' into semantic-outline

Conflicts:
	org.strategoxt.imp.runtime/src/org/strategoxt/imp/runtime/editor/SpoofaxViewer.java
Extracted generic code used for both the Outline View and the Quick Outline. Removed esv-based outline backwards compatibility.
No more delay on editor start-up.
Bugfix: text selection to outline selection gave error when outline page was loaded, but outline was still null.
undefined outline-strategy message
Quick Outline: text selection upon outline node selection.
Moved outline-library to new runtime libraries
Heuristic-based outline generated (based on new outline stuff)
bugfix
fix
Brought back the esv-based outline for backward compatibility.
Workaround for bug in StrategoTermPath.getTermPathWithOrigin(..)
Bugfix: selected element in quick outline can be null
Heuristic-based outline: generate 'label-outline = fail' in case of no
rtg-prods.
fix
Outline: use origin-text at start of stratego appl in case none of the symbols is an outline label candidate
Heuristic outline: small improvements
Label provider: fallback in case label is not a string
Outline: reuse heuristic-sort-is-identifier