Add support for specifying the revision number in a source: link for the Image macro.
Add support for specifying the revision number in a source: link for the Image macro.

E.g. `source:path/to/image@rev`

Suggested by Eugene Atroshkin.



git-svn-id: f68c6b3b1dcd5d00a2560c384475aaef3bc99487@2904 af82e41b-90c4-0310-8c96-b1721e28e2e2

dokipen/trac,dokipen/trac,moreati/trac-gitsvn,exocad/exotrac,exocad/exotrac,moreati/trac-gitsvn,dafrito/trac-mirror,dafrito/trac-mirror,dafrito/trac-mirror,moreati/trac-gitsvn,exocad/exotrac,dokipen/trac,moreati/trac-gitsvn,exocad/exotrac,dafrito/trac-mirror