Add packaging to GAV in key map

[slawekjaranowski]

Currently in key map we have format:

groupId:artifactId:version = keyId

We want extend it to:

groupId:artifactId:packaging:version = keyId

where groupId is mandatory and other field are optional.
In groupId, artifactId, packaging - we can use * or any other regular expression
version can be specified as maven version syntax

There are case where pom file has signature but jar hasn't.

It will be good to prepare separate site with description of key map file syntax.