0.3.0 Released

Code cleanup. Stability fixes (how many times have we heard that one...). Idle transfer operations can now be cancelled (Arc::DataMover does not support the cancel operation in 2.0. Will be implemented in next ARC). Graphical status of transfers in transfer list window. Buttons for canceling single transfers. Proxy will be created directly from application when needed. Window positions are also stored with the last opened url. Closing the main window will remember client window position and state.