Merge pull request #131 from ngunn/dev

List.js: fix long-standing bug in append (2 chr$ change)
Move LineStyle into Collage.
Merge branch 'dev' of https://github.com/evancz/Elm into dev
Fix rendering of lineJoin.
Show.js: add "undefined" as possible output in toString
Otherwise toString throws an error caused by "k in v".
Rationale: even if everything is going horribly wrong, it's still useful to be able to see stuff
List.js fixes
All tested in file: https://gist.github.com/ngunn/5253583

Added:
  comment on Nil handling
  missing and and or functions

Changed:
  direct Nil comparison with ctor equiv.  see comments here: https://github.com/evancz/Elm/pull/130#issuecomment-15471337
  split function (rewritten).  previous split failed 11/18 tests (see gist for tests).  eg, split "aa" "a" generated an error

 List.elm: Uncommented type sigs (didn't see the harm...)
Setup.hs: move buildTypes back into post-build, fixes compilation dependencies
cabal compiling far fewer files now :-)
minimal changes, mostly comments, so it should be easier to put back/further fix/other