{feature}-installer.zip not copied to sdnc-img

{feature}-installer.zip not copied to sdnc-img

The "generate-sources" phase assigned to
docker-maven-plugin occurs much earlier
than phase of for building and staging
*-installer zip files. This leads to
image not having any of these zip, thus
ODL inside sdnc containers fails to load
sdnc feature repos.

The right Maven lifecycle phase for building
docker should be "package" as this creates
docker-build.tar.

Also, removed the redundant file permission
change in Dockerfile

Change-Id: If951e97dd9568343a577e64a8dd9452aaf74557d
Signed-off-by: Rashmi Pujar <rashmi.pujar@bell.ca>