gplugin/gplugin

Remove the mingw-cross packaging stuff as we're probably never going to get it working right

Testing Done:
Nothing

Reviewed at https://reviews.imfreedom.org/r/962/
REVIEWBOARD_URL = "https://reviews.imfreedom.org/"
REPOSITORY = "gplugin/gplugin"
REPOSITORY_TYPE = "mercurial"
BRANCH = "default"
LAND_DEST_BRANCH = "default"
LAND_PUSH = False