Added test files for specifying a root_patch_dir

We need to be able to go into the patch dir and use a specific source if
needed. This change puts all the tests in place to do that.
Added ability to specify patch blob directory

Since some diffs create hierarchies with extra folders, this allows us
to specify where in the dir we want to yank the patches out of.
Merge pull request #11 from endlessm/eos-shell/2654

AppUpdater: Added ability to specify patch blob directory