gnupg: 2.1.22 -> 2.1.23

This release in a RC for gnupg-2.2. The main difference as far as
nixpkgs is concerned is that the binary `gpg2` is now called `gpg` and
`gpgv2` is called `gpgv`.

This update fixed all explicit use of `gpg2` and `gpgv2` across nixpkgs,
but there might be some packaged software that internally use `gpg2`
not handeled by this commit.

See http://lists.gnu.org/archive/html/info-gnu/2017-08/msg00001.html
for full release information

pkgs/applications/networking/browsers/firefox-bin/update.nix

@@ -22,7 +22,7 @@ in writeScript "update-${name}" ''
   pushd ${basePath}
 
   HOME=`mktemp -d`
-  cat ${./firefox.key} | gpg2 --import
+  cat ${./firefox.key} | gpg --import
 
   tmpfile=`mktemp`
   url=${baseUrl}
@@ -47,7 +47,7 @@ in writeScript "update-${name}" ''
 
   curl --silent -o $HOME/shasums "$url$version/SHA512SUMS"
   curl --silent -o $HOME/shasums.asc "$url$version/SHA512SUMS.asc"
-  gpgv2 --keyring=$HOME/.gnupg/pubring.kbx $HOME/shasums.asc $HOME/shasums
+  gpgv --keyring=$HOME/.gnupg/pubring.kbx $HOME/shasums.asc $HOME/shasums
 
   # this is a list of sha512 and tarballs for both arches
   shasums=`cat $HOME/shasums`