Merge pull request #22 from gaya-/master

[reasoning] improved predicate LISP-FUN
[desigs] optional format statement for validation functions
Moved the macro HANGS into CRAM_LANGUAGE_TESTS

The macro is quite specific for cram_language, namely,
the constants and the logging mechanism.
Merge branch 'master' of https://github.com/cram-code/cram_core