wheezy/*/.gitkeep: create placeholders for empty directories

This fixes #1.

Files created by:

    find wheezy -depth -empty -type d -exec touch "{}/.gitkeep" \;

Signed-off-by: Paul Campbell <paulcampbell@fife.ac.uk>
Merge pull request #2 from FifeCollege/fix/bug-1

wheezy/*/.gitkeep: create placeholders for empty directories