Doxygen documentation support

To run:
Enter Core directory
run 'doxygen' on a terminal
Android: Fix classpath so indexing works for the core project
Mission: Add the change speed mission item
Test: Added unit test for ChangeSpeed
Android: Fix orphan string
Editor: Add the Change Speed item to the editor
Merge pull request #1202 from DroidPlanner/doChangeSpeed

Do change speed
Dronie: Slow down the drone as it reaches the final dronie mission
Dronie: Update the map when the dronie is sent to the copter
fixed unit for the change speed mission item.
Update MissionItemType.java
Default cross-hatch to false
Update UI to change name of scan option to "Structure Scan
add dialog to confirm dronie creation, and tell the use where to stand.
Merge pull request #1204 from zlite/patch-1

UI changes to scan option
rotate the screen in the direction the dronie is headed.
code cleanup.
Merge pull request #1203 from DroidPlanner/dronieUpdate

Dronie update
Version: Releasing version 2.8.1
Android: Fix string on Magnetomer calibration