[minor correction] package.xml with repeated dependencies

[TSC21]

In https://github.com/vooon/mavros/blob/master/mavros/package.xml.
Removing ambigual build_depend, it will stay like this:

  <buildtool_depend>catkin</buildtool_depend>
  <build_depend>boost</build_depend>
  <build_depend>diagnostic_msgs</build_depend>
  <build_depend>diagnostic_updater</build_depend>
  <build_depend>message_generation</build_depend>
  <build_depend>pluginlib</build_depend>
  <build_depend>roscpp</build_depend>
  <build_depend>rospy</build_depend>
  <build_depend>geometry_msgs</build_depend>
  <build_depend>sensor_msgs</build_depend>
  <build_depend>std_msgs</build_depend>
  <build_depend>tf</build_depend>
  <build_depend>mavlink</build_depend>
  <build_depend>angles</build_depend>
  <test_depend>gtest</test_depend>

Can you check?

[TSC21]

By the way, what's the problem with Travis CI build, which cannot compile?

[vooon]

It use old mavlink deb.

Now wiki.ros.org recommend package.xml version 2, but tools don't generate it now (but support).
It can reduce depend tags.

[TSC21]

Oh ok. It doesn't really matter is just a thing of organisation.