Allow arbitrary source archive name to be imported into Dockerfile

Currently we cannot import source archives with names different
than expected by hardcoded line in Dockerfiles. This worked well
for Openstack services' tarballs where we expected SERVICE-* root
folder after extraction or kanaka-noVNC for nova-novncproxy docker.
The latter fails if one tries to clone or get tarball under other
names. This fix allows any archive (tar,tgz,zip) or repo name to be
imported into dockerfile.

Change-Id: I869a6a19afaf0e93925572746c22b7589b6600c9
Closes-Bug: #1491415