pcre: Adding 16 and 32 bit switches so it can use the respective charact...

...er bit width.

Adding libbz2 and libz switches so it can read thir respective compressed file formats.
Grep appears to be fine with them, not run into any issues.

Not sure if we want or need --enable-pcretest-libreadline. It adds line editing and history
features to pcretest program.