Added transact demo project
Ported MultiSwingView to transact

Not yet tested, provides per-class views as in core implementation, but
not per-instance views - they are trickier to implement, and swing
memory leaks (from swing creating lots of pointless references) make
them much less useful than you would expect. Per-instance view settings
in "view-model" are much better.
Work on path implicits, boolean view

Core SineDemo has neater code for paths using map rather than
comprehension.
Still trying to make transact implicits for paths work well :(
Shared code for properties sheet editor in transact SineDemo, added
extra tab. Started porting graph stuff, but first need to move SineDemo
to transact demo project to pick up graph dependencies.
Split BooleanView factory methods into an apply for most uses (slide
check) and an extended method if you really want old-style checkboxes
etc.