Quickly

- still pre-alpha but work in progress
- quickly.dom.lily now has much more elements
- correctly parse lists, property paths etc
- added chordmode and chord modifiers, figuremode
- quickly.lang.lilypond now transforms almost a full document
- commands are combined with their arguments, based on signatures
- work started on documentation with a quickly.dom explanation

- still pre-alpha
- much more robust already
- dom.element now has the four basic Element node types
- dom.element can be constructed manually or via LilyPondTransform
- writing back to document works
- scheme expressions are fully read/built
- markup expressions are fully read/built
- complex articulations, tweak, tremolo etc. work well
- toplevel and in block assignment is wrapped in Assignment node
- lyricmode and drummode work
- todo: music functions
- some test files were added. todo: more test files
- module documentation in good shape. todo: user documentation