Fix #12 -  Archetypes displayed in wizard not always consistent

Add the Adobe Public Repository as an archetype catalog by default,
making sure that we always have a good source of archetypes.
Affects #12 -  Archetypes displayed in wizard not always consistent

It's no longer necessary to embed the archetype since we enable the
repo.adobe.com archetype catalog by default
Fix #15 - Support m2e 1.6 or newer

Use Require-Bundle instead of Import-Package for stuff provided by m2e .
This works around that org.apache.maven, org.codehaus and other packages
are exported with mandatory provider=m2e attribute.