Mingw32 package for GnuPG

An installed GnuPG will be picked up by mgwport and allows to check the signature
of a downloaded archive during package building.

For example after installing GnuPG:
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$ mgwport gnupg-1.4.13-1.mgwport prep
>>> Preparing gnupg-1.4.13-1
*** Info: SOURCE 1 signature follows:
gpg: Signature made 12/20/12 20:48:35 using RSA key ID 4F25E3B6
gpg: Good signature from "Werner Koch (dist sig)"
gpg: WARNING: This key is not certified with a trusted signature!
gpg:          There is no indication that the signature belongs to the owner.
Primary key fingerprint: D869 2123 C406 5DEA 5E0F  3AB5 249B 39D2 4F25 E3B6
>>> Unpacking source gnupg-1.4.13.tar.bz2
>>> Preparing working source directory
------------------------

The version of GnuPG is rather old, because newer versions are split into very many
different libraries, so the hassle to build them is much bigger.

Signed-off-by: Thomas Braun <thomas.braun@virtuell-zuhause.de>
Merge pull request #7 from t-b/mingw32-gnupg-v2

Mingw32 package for GnuPG