A lot new methods/class added and many cleanups:

A lot new methods/class added and many cleanups:
- Double-quotes converted to single to speed-up things a little
- Wrong BaseconnectionInstance fixed
- New methods introduced to cruncher:
  + doFetchWorkUnits(): To fetch WUs or generate test units
  + enableIsActive/isActive(): To test/set if the cruncher is active
  + initBufferQueues(): To initialize in/out buffer queues
- addExtraCruncherFilters() renamed to addExtraFilters()
- This method has now project-wide a Controller instance as first argument
- Dublicate method call to addExtraFilters() removed which happens in the
  rewriting process
- $appInstance renamed to $applicationInstance to have a better naming
  convention
- Some deprecated classes removed (they where named wrong)
- BaseHubCruncher (a generic class) extended:
  + It does now check if the in-buffer queue is filled (depending on a
    configurable threshold)
  + It implements initBufferQueues() from CruncherHelper interface
- Copyright fixed in HubMcryptCruncher
- The idle-loop task is now "genericly" registered in the TaskHandler class:
  + This implies that all task-based application will always have at least
    one (but really generic) task.
  + The method hasTasksLeft() will return 'true' in all situations unless the
    idle-loop task "kills" itself
- Generic cruncher-activation filter added
- The mentioned buffer queues are now initialized by a newly added filter class
  and handled by an own task class
- More minor code-cleanups
- TODOs.txt updated