[*] Updated declarations for LTK-2.2

Signed-off-by: Stephan Wahlbrink <sw@wahlbrink.eu>
[LTK-Editor] Consolidated command definitions

Signed-off-by: Stephan Wahlbrink <sw@wahlbrink.eu>
[LTK-Editor] Added definition of strip comments commands and generic
handler for model based operations

Signed-off-by: Stephan Wahlbrink <sw@wahlbrink.eu>
[LTK-Editor] Added support for persistent code folding

Signed-off-by: Stephan Wahlbrink <sw@wahlbrink.eu>
[LTK-Model] Extracted generic parts from refactoring package

Signed-off-by: Stephan Wahlbrink <sw@wahlbrink.eu>
[LTK-Text] Added minor improvements

Signed-off-by: Stephan Wahlbrink <sw@wahlbrink.eu>
[LTK-Model] Refactored LTK-Model definition and links content types
  - Added content type to source unit
  - Moved content type activation to model definition
  - Renamed model extension point

Signed-off-by: Stephan Wahlbrink <sw@wahlbrink.eu>
[*] Updated build configuration
  - Updated to Tycho-0.17

Signed-off-by: Stephan Wahlbrink <sw@wahlbrink.eu>