Provide necessary licensing files in features using license-feature.

Provide necessary licensing files in features using license-feature.

Create org.eclipse.linuxtools.license.feature which packages
epl-v10.html and license.html files.  Reference this feature using
'license-feature' in other features to have the necessary files appear
in binary/source features.

Change-Id: I2fd6ea0bbe47b290625920c0bf5edd35c5d360c4
Reviewed-on: https://git.eclipse.org/r/14014
Tested-by: Hudson CI
Reviewed-by: Camilo Bernal <cabernal@redhat.com>
IP-Clean: Camilo Bernal <cabernal@redhat.com>
Tested-by: Camilo Bernal <cabernal@redhat.com>