Fix errors in generated code when MAVLINK_CRC_EXTRA is disabled

Also ensures that packet length parameters use the appropriate *_LEN define
instead of hardcoding the raw values.
Clarified units for latitute/longitude/altitude in various messages.
Python generator: allow for hex and binary notation in enum value attributes (and longer ints).
Fixed error received when running mavlogdump.py when processing invalid messages that contained a non-ASCII value.
Merge branch 'master' of https://github.com/mavlink/mavlink into inv_char_fix
Merge pull request #119 from Susurrus/inv_char_fix

Fixed issue with printing MAVLink_bad_data
Merge pull request #118 from AutoQuad/upstream

Python gen: allow for hex and binary notation in enum value attributes
Merge pull request #113 from Susurrus/new_issue_92

Clarified units for latitute/longitude/altitude in various messages.
Merge pull request #106 from RFDesign/upstream

Fix errors in generated code when MAVLINK_CRC_EXTRA is disabled
Merge branch 'master' of https://github.com/mavlink/mavlink