APRS Daemon

I am nearly finished with the APRS daemon. Currently, a check for active flights is only performed on startup. There are a few things I need to tweak, but that is for later.

Here is what the typical output is like:
```
$ hp ~/dev/habitat/bin/aprs_importer
[2013-02-21 01:13:53,796] INFO habitat.utils.startup MainThread: Log initialised
[2013-02-21 01:13:53,861] INFO habitat.aprs_daemon MainThread: Checking for active flights
[2013-02-21 01:13:53,872] INFO habitat.aprs_daemon MainThread: 0 active flights with 1 callsigns
[2013-02-21 01:13:53,872] INFO habitat.aprs MainThread: Setting filter to: b/LZ1DEV
[2013-02-21 01:13:53,872] INFO habitat.aprs MainThread: Attempting connection to first.aprs.net:14580
[2013-02-21 01:13:54,375] INFO habitat.aprs MainThread: Sending login information
[2013-02-21 01:13:54,488] INFO habitat.aprs MainThread: Login successful
[2013-02-21 01:14:04,999] INFO habitat.aprs MainThread: Parsing: LZ1DEV>APU25N,TCPIP*,qAC,THIRD:=/8sweTCpK-  BRTL-SDR RX-only
[2013-02-21 01:14:05,001] DEBUG habitat.aprs MainThread: ParseError: unknown format
[2013-02-21 01:15:07,067] INFO habitat.aprs MainThread: Parsing: LZ1DEV>APU25N,TCPIP*,qAC,THIRD:=4241.81N/02317.93E-RTL-SDR RX-only
[2013-02-21 01:15:07,068] DEBUG habitat.aprs MainThread: Parsing as normal uncompressed format
[2013-02-21 01:15:07,068] INFO habitat.aprs MainThread: Parsed ok.
[2013-02-21 01:15:07,703] ERROR habitat.aprs_daemon MainThread: {"error":"forbidden","reason":"New documents may only have _raw in data."}
```

Uploading `listener_telemetry` for `chasers` is ok, However, when I try to create a `payload_telemetry` doc, it fails with the error above. I figure, it is because how the `parser` is designed. How can we make it work ?