Revert "Merge pull request #281 from tuncer/rebar-h-internal"

This reverts commit 07e2232847baa634b7d09bdb87dafda6c6bcc4a4, reversing
changes made to 37cf470ae9a07cdd2e0769f3af9a8b89fcde8db0.
Bump to 2.5.0
Add {prefix, atom()} option for abnfc_opts

Specify the atom to use as a prefix for the decoder and generator
functions inside the parser's module.  Default is ''.
Add {parser, module()} option for abnfc_opts

Specify the module to use for parsing the ABNF grammars.  Default is
'abnfc_rfc4234'.
Add {qc, proplist()} option for abnfc_opts

Specify the options to use for the generator functions inside the
parser's module.  Default is [].