iRODS support with autoconf RFC

An initial pass at adding configuration support for iRODS using autoconf. The intention
is that aside from running autoconf, all previous Makefile behaviour is preserved.

- The original Makefile becomes Makefile.in, preserving the custom
  build behaviour. The package version and SO version are configured
  in configure.ac.

- iRODS is off by default and enabled using --with-irods=/path/to/irods

- A -O <output file> option has been added to test_view and
  "test_view.pl irods" will run test_view.pl as normal, but writing
  its results directly into iRODS.