bug#26610: python-gpg broke; python-gpg 1.9.0 does not exist

[Christopher Allan Webber]

Commit 8439c9c05e upgraded gpgme to 1.9.0.

Unfortunately, python-gpg's version is tied to gpgme:

(define-public python-gpg
  (package
    (name "python-gpg")
    (version (package-version gpgme))
    ;; [...]

This is a problem, because upgrading gpgme "automatically" upgraded
python-gpg, and there is no python-gpg release of 1.9.0.  The latest
release is 1.8.0:

  https://pypi.python.org/pypi/gpg/1.8.0

I'm not sure it makes sense to tie the package version to python-gpg's
package version anyway... if upgrading gpgme does trigger the upgrade of
python-gpg "automatically", then that would mean that even if there was
a pythong-gpg available with the new version, the hash would be
incorrect.