Initial commit
Only use getopt_long when long options present
Made install target dependent on compiled binary
Removed incorrect comment about "-A"

- Originally had a comment referring to "-A" as non-POSIX, but "-A" is
  part of the newer POSIX standards.
Improved man page parsing

- CLI options can now be parsed from either the DESCRIPTION or OPTIONS
  sections of man pages.
- Parsing now works with man pages that use Unicode minus (\u2212).
Fixed typo in README.md
Added support for mawk

- Per https://bugs.launchpad.net/ubuntu/+source/mawk/+bug/69724, mawk
  does not support POSIX character classes. The Makefile has been
  modified to detect this and patch parseopts.awk accordingly.