Record and playback tools comitted to Subversion

I've created a tool(recorder.py) now that records GPS-sentences and the delta time between two sentences. Another tool(playback.py) plays back the GPS-sentences with the same delta time delay between sentences. The timing during playback is not 100% accurate since the OS both at recording and playback is not 100% accurate and I've not taken into consideration that transfer of a sentence from a GPS-unit to a host take time (varies by baudrate). The playback is done with FIFO and only tested on MacOSX. The recording is only tested on WinXPSP2.