classloader tweak so Travis will stop failing
package renaming: parse0 -> parse, parse -> compile.front

I was always unhappy with "parse0", I just didn't have a better
idea... until now!
whoops, unintended change sneaked into last commit
fiddling with the graffle as usual
pull common infrastructure out of compile.front

and cut dependencies between compiler subpackages where possible.
see project/Depend.scala changes (and graffle changes) for the
new structure.  front, middle, back each independent, and only
front depends on parse
Merge branch 'headless' into tortoise