Added asset-transfers, debug delegate, small fixes

- Asset-transfers added.
- Debug delegate added, users can provide a handler-method to display or
log debug info.
- Added username parsing from transfer-orders in order-history (new BTCT
API feature).
- Small fixes
Added  automated asset-transfers

- Added functionality that periodically loads the trade history and
submits transferred orders to other users that transferred a specific
asset to the user. Intended application: Deprived Mining Speculation
(DMS) transfers.
- A messagebox now shows instructions when obtaining request token.
- Support for writing all output to a log-file.
- Minor fixes.