[DH] Fix for time signature setting from scoreDef
added test and fixed missing update of scoreDef object
another test for staffInfo behaviour
Slicing staffInfo parameters only effect first scoreDef
Merge pull request #65 from zolaemil/timesig

improving scoreDef attribute handling
consider staff/@n for ties
Merge pull request #66 from zolaemil/tie-fix

consider staff/@n for ties
added check for undefined-error in slurs
handle undefined-error in tie/slur calculation
Merge remote-tracking branch 'upstream/master' into upstream

Conflicts:
	src/Converter.js
	src/LinkCollections.js
added logging levels
added autostem option to VF.Beam
changed error handling
added longa to duration aliases
additions to staffDef inclusion in staffInfo
added new clefs; changed clef conversion
dropped support for tuplets in grace notes
rest-w/o-ledger-line now in vf -> removed workaround
set auto_stem in beams only if no stem.dir has been specified
added support for key sigs in all clefs (TODO octave position)