Added publish.sh script for generating P2 metadata for a set of bundles
The P2 repository generated will be published at
http://www.simantics.org/download<branch>/external-components/manual.
Also added composite P2 repository descriptors that will be published at
http://www.simantics.org/download/<branch>/external-components/. This
composite repository includes both the previously mentioned manual
direcotry and its sibling P2 repository called maven.