Code Generator for Eclipse Code

Refactored CodegenPlugin to seperate the UI components and mov them into the ui plug-in

Resolved the problem of an error when adding the import from a reference implementation (#36)

Completed implementation of selecting the reference implementation from a drop down list (#20)

Added extension point definition and the corrisponding helper class for #22

Validate the page after removing a row. This concludes #22.

Fixed part of the problem that is addressed in #22: Ensure, that when an item is removed from the table it is also removed from the backing model, therby inhibiting the generation of the removed artifact.

Refactoring Logging: Made logging method member methods

Refactoring based on the moving of three classes

Removed the input fields for the generator class. This is part of #21

Removed the input fields for the jetemplate. This is part of #21