More functions in libtc

Version 0.2.0 is released. It contains several useful functions from glibc 2.1.3:
- reentrant hash table functions (hcreate_r, hsearch_r)
- tdestroy
- strsep, BSD string tokenizer
- reentrant strtok_r

Libtc now uses autoconf and compiles on Linux, SunOS, Digital UNIX and possibly others.