change en-test.o.o mediawiki_src to /usr/share/mediawiki_1_27--git/
This allows fast and easy deployment of changes in
https://github.com/openSUSE/wiki/ on en-test.o.o without updating the
mediawiki_1_27-openSUSE package.
The big advantage is that it allows testing of skin updates etc. without
risking breakage on the production wikis.
Note that (and that's the shocking part of this commit ;-)
/usr/share/mediawiki_1_27--git/ needs to be `git clone`d manually, and
also needs several symlinks to /usr/share/mediawiki_1_27/