Code Generator for Eclipse Code

Export internal package for test plugin

Refactoring towards the use of builders

Updated ther version number to 2.1.0

Merged from branch UI_seperation_II

Do not export org.eclipse.emf.codegen in ch.sahits.codegen

Do not reexport the plugins org.eclipse.ui and org.eclipse.help in ch.sahits.codegen.help

Refactoring Logging: Made logging method member methods

Removed the qualifier from the version number since the update site could not cope with it

Added qualifier to version

Set the verions dependencies for sahits plugin explicitly and otherwise none