scripts: Add mavsetp script.

Only local setpoint for now.
Issue #126.
plugin: command: Add guided_enable shortcut

It enable PX4 OFFBOARD mode.

Issue #126.
scripts: mavsetp: Enable OFFBOARD mode.

Issue #126.
travis: disable mavlink hack
plugins: setpoint: Update SET_POSITION_TARGET_LOCAL_NED message.

Fix #131.
Prepare minor release 0.7.1
0.7.1
plugin: command: Add COMMAND_INT suport.

Fix #98.
node: Catch DeviceError; use C++11 foreach shugar.
travis: Use ros-shadow-fixed repo for builds
Merge branch 'master' into coverity_scan

* master:
  travis: Use ros-shadow-fixed repo for builds
  node: Catch DeviceError; use C++11 foreach shugar.
  plugin: command: Add COMMAND_INT suport.
  0.7.1
  Prepare minor release 0.7.1
  plugins: setpoint: Update SET_POSITION_TARGET_LOCAL_NED message.
  travis: disable mavlink hack
  scripts: mavsetp: Enable OFFBOARD mode.
  plugin: command: Add guided_enable shortcut
  scripts: Add mavsetp script.