Added project, project creator, and constants

Also added some more functionality to Import RPMs page buttons
to remove RPMs from the list as well as the project.

Projects will contain basic functionality of the command and will
contain the directory structure of the project.

TODO: need to implement a resourceChangeListener on POST_CHANGE to
    watch for changes in the project (i.e., deleting RPMs in the
    project will automatically update the tree of RPMs and remove
    the ones deleted).

    OR probably just not link the tree with the
    project at all and let the user fully control the specific RPMs
    from the project he/she wants to creat a repo for. (Createrepo
    has the -i --pkglist command to specify RPMs to include)

Signed-off-by: Neil Guzman <nguzman@redhat.com>