Renamed directories: core -> backend, view -> frontend-qt
Moved the backend and frontend in respective libraries. (don't compile yet)
Fixed: missing header files in backend.
Removed references to Qt in backend.
Moved paths definitions into backend.
Fixed includes in backend.
Renamed aosd::core namespace to aosd::backend
Renamed aosd::core namespace to aosd::backend
Added missing headers in backend.
Renamed backend header guards, removed functions referencing "view", renamed aosd::core to aosd::backend namespace.
Fixed #16: don't create a new sequence on project creation.