Maven: generate Maven repo from list of Ceylon modules

[FroMage]

In order to export to Maven Central it's useful to be able to generate a Maven repo from a list of already compiled Ceylon modules. Including to publish the distrib.

This requires that we add the missing pom.xml to the distrib jars. We should generate them from the module.xml included, except those don't contain the groupId/artifactId coordinates for the modules which do come from Maven, such as aether.

[FroMage]

This seems to work now, but I still have to publish the test.

[gavinking]

Excellent :)

[FroMage]

Done.