Added status from mavlink

Added basic support for status (warnings) from mavlink to taranis.
Reusing Temp2 to send both warning status and armed. Added on output to
the ApmTelem-mixer script to make armed available as an input (since
temp2 can't be used any more).
Read bmp-files from /BMP/

Correct location for bmp's.
Bugfix in error reporting.
Test of status text parsing

Initial support for parsing status text and converting it to a number.
Merge pull request #6 from chsw/master

Pull from chsw/MavLink_FrSkySPort