Add a new 'is_topdir' argument to the GitRepo init method which
validates that the given path is the top directory of a Git repository.
Without this argument GitRepo also accepts subdirectories of a Git
repository (in which case GitRepo will point to the parent directory
that is the top directory of this repository) which may have undesired
in some cases.
Signed-off-by: Markus Lehtonen <markus.lehtonen@linux.intel.com> Signed-off-by: Ross Burton <ross.burton@intel.com>
