- Merge Timeline::STATE_MOVING_LAYER/CEL/FRAME to STATE_MOVING_RANGE.
- Remove celmove.h/cpp and move_cel/copy_cel functions. Now they are
in the Timeline as dropRange/Cels/Frames/Layers member functions.
- Add DocumentApi::copyFrame/moveCel/copyCel member functions.
- Add timeline_drop_layer_deco and timeline_drop_frame_deco skin parts.
- Move code from DuplicateLayerCommand::onExecute() to new member
function DocumentApi::duplicateLayer().
- Fix a bug changing Cel's frame number: we weren't updating the Cel
position properly inside the LayerImage::m_cels collection. Now we use
LayerImage::moveCel() to change the Cel frame number.
- Other fixes to DocumentApi: Change bgcolor from int to color_t.
- Add HAVE_CONFIG_H wrapper to #include "config.h"
- Removed widgets namespace (it's in app now)
- Move some functions from src/file/file.h to src/base/cfile.h
- Move Vector2d to base library
- Rename MenuItem2 to AppMenuItem