Languages harness

There are 4 ways to run a language test:

Overall Harness
    make languages-test
or
    cd languages && make test
Selected languages
    cd languages && perl t/harness --languages=pynie,punie
Per Language Harness
For almost all languages you can do something like:
    cd languages/tcl && make test
Run a single test for more detailed output.
    cd languages/tcl && prove -v t/cmd_lsort.t

TODO

It should be possible to use non-Perl5 test files, like for languages/perl6 or languages/pheme.

We are assuming that we are running out of parrot/languages; we are being called by languages/Makefile with an explicit perl.