--out-dir option

Still prepends g_ if the option is not given.
improve the test harness --> dump harness

takes 'debug' or 'release' so only one to mantain and uses --out-dir to
put the files in \gen directory.
fix bug in out-dir

confused when directory already exists.
new test suite: syntax_check

For the tests that should fully compile, like test_007 we run the VS2013
compiler with Zs (syntax check).
clean up bugs

that are done.