Sync with my GitHub branch.
Sync with upstream.

 branch 'upstream/master'

# Please enter a commit message to explain why this merge is necessary,
# especially if it merges an updated upstream into a topic branch.
#
# Lines starting with '#' will be ignored, and an empty message aborts
# the commit.
Merge https://github.com/stambaughw/MINGW-packages
Add documentation and remove redundant install prefix from KiCad package.
Merge pull request #327 from stambaughw/master

Add docs to KiCad package.