Version-specific p2 repository URLs make "Check for updates" fail

[oberlies]

The m2e connectors catalogue currently seems to contain the source URL http://repo1.maven.org/maven2/.m2e/connectors/m2eclipse-tycho/0.6.0/N/0.6.0.201207302152/ for the Tycho connector.

This URL seems to be specific to exactly one version of the Tycho connector.

When a new m2e version requiring an updated Tycho connector is published, "Check for updates" in Eclipse would fail. This is because p2 would find the updates for m2e but not the updates for the Tycho connector.

I think that the connectors catalogue should contain a stable URL that contains all versions of the Tycho connector.