Improve README
Travis CI: Test flight tester email notification
Travis CI: Fix email line
Travis CI: Next attempt at email notification
Travis CI: Next attempt at email notification - avoid env var.
Travis CI: We need mailutils
Travis CI: Change binary file name
Merge pull request #1524 from PX4/prtest

Improve README
branch manual_slip: add manual control of rudder in stabilized modes
add interrupt latency printout command and mean/variance to interval performance counter
fix typo in comment
WIP: dynamic estimation of baro_gps_offset