Make ./pants run work for scala.

Unclear how (or even if) this ever worked before.
Style nit per code review comments.
Remove 3rdparty targets used by commons but not pants.
doc: start a Pants-with-IntelliJ page

Full disclosure: I don't know IntelliJ myself. This change's content mostly plagiarized from some guy named Benjy Weinberger.
Make jvm run work with scala.
Remove 3rdparty/BUILD entries pants doesn't need.
docs: += better advice for recovering from losing the publishing race
Pants help text += link to web site
Ensure an integer for chunk_count.
Fixup nailgun detection under unicode literals.

Unicode literals in the NailgunExecutor command line
did not interact well with psutil - use byte strings
for these.

Also kill conditional psutil related code since its
now always available.

Finally - fixup the ci script jvm target.
Eliminate import failure handling for colors - this is now always available.
Fix a bug in jvm_compile.

Not all JVM languages have runtime deps.
Fixes to diffing code.
Merge branch 'master' into zinc_analysis_test
Fix zinc analysis split.