[LTP] new shell library

[Cyril Hrubis]

Hi!
Just FYI, I've added support for positional arguments, since many shell
tests use these, and tried to convert two of these. See:

https://github.com/metan-ucw/ltp/commit/3860c62e4f1ca6aa2f352ec50dd7087fa75b4487
https://github.com/metan-ucw/ltp/commit/5203cc54bbc64125a1c18ab93a4d13347609dc6e
https://github.com/metan-ucw/ltp/commit/3b7092f76e183627b3bb028bd5a8064e518d469a

-- 
Cyril Hrubis
chrubis@suse.cz