Moves content of core.api in core, and adds Ixxx prefix
Switches to package import for the dependency to osgi.service.location

The dependency to the bundle org.eclipse.osgi was creating conflict
with the bundle javax.xml.bind (included in Eclipse for JEE).
Merge pull request #779 from skyluc/issue/API-ScalaProject-location

Moves content of core.api in core, and adds Ixxx prefix
Merge pull request #780 from skyluc/issue/java-xml-dep-conflict

Switches to package import for the dependency to osgi.service.location