update version for the next beta release.
Added 'AutopilotWarningParaser' interface. It'll be used to provide platform specific implementation warning parser implementation.
Added a 'AutopilotWarningParser' field to the Drone State component.
added stub android implementation of the 'AutopilotWarningParser' interface.
update source compatibility to java 1.7
removed deprecated functions from the aidl interfaces.
updated aidl interface implementation to account for the removal of the deprecated functions.
added methods to retrieve the service, and the client library version.
added asynchronous methods to access the drone attributes.
removed deprecated methods from the drone api lib.
client lib async api bug fix.
update default values for the StreamRates, State, and Type drone properties.
added default implementation of the OnAttributeRetrievedCallback interface.
updated client library version number.
increase the number of threads used to retrieve drone properties.
api and version update.
removed 'ping' methods from the aidl interface as the api provides a similar functionality.
updated the service, and client implementation to make use of the IBinder api for notification on IPC process lifetime events.
bug fixes.
Merge pull request #15 from DroidPlanner/cleaning_deprecated_functions

Cleaning deprecated functions
updated the toString method for the VehicleMode, and the MissionItemType enums.
 update the androidJavadocs generation task.
 added script to automatically push the generated javadoc to github.
updated the location of the javadocs directory.
testing travis upload of the javadoc to the gh_pages branch.