Document compile_only=true
Remove experimental flags

Remove experimental flag from:
* qc compile_only=true
* eunit compile_only=true
* src/foo.app.src.script
* eunit tests=
Fix basho/rebar#388

If the syntax error is in a .hrl file, then the reported error message
is not as useful because it's not clear which .erl file was being
compiled. We can fix that easily by first printing what source file was
being processed. We don't change the actual error message, so this will
still work with your editor of choice for jumping to the right line.

Before
------

Success:
Compiled src/foo.erl

Failure:
include/foo.hrl:10: syntax error [...]

After
-----

Success:
Compiled src/foo.erl

Failure:
Compiling src/foo.erl failed:
include/foo.hrl:10: syntax error [...]
rebar_base_compiler: replace fixed size list with a tuple
Merge pull request #214 from tuncer/compile_only

Document compile_only=true
Merge pull request #215 from tuncer/experimental

Remove experimental flags
Merge pull request #212 from tuncer/hrl-error

Fix basho/rebar#388