Remove unnecessary activator
Revert "Remove unnecessary activator"

This reverts commit 50275bf691ee21f45e5f298c737e70679ca63712.
Preference spy adjusted 

Adds Preference page
Listener on this preference
Deregisters listener if deactivated
Removes Action
Improves class name for Preference page
Moves preferences spy to subfolder
Added Feature
Changed version of the plugin from 1.0.0 to 0.1.0
Changed version of feature from 1.0.0 to 0.1.0
Adds build infrastructure to preferencesspy
Adds P2 Repository to the buildprocess
Adds bin folder to .gitignore
Removes bin folder which a85d136a0 introduced

Fixes #2
Cleanup of the Activator class
Adds custom dialog to show preferences

Fixes #3
Display of preference values now correct.