Jenkins 11952 debug

NOT INTENDED FOR MERGING - just wanting a CI built version of the plugin for others to test with.

List connected adb devices whilst waiting for bootcomplete.
This should give us some better clues as to what is going on.

The interesting output that you will see in the console logs is as follows (the exact details will vary)

    $ /opt/android/android-sdk-20-linux_x86/platform-tools/adb connect emulator-5607
    [android] Waiting for emulator to finish booting...
    $ /opt/android/android-sdk-20-linux_x86/platform-tools/adb devices -l
    List of devices attached 
    emulator-5607          offline
    
    [android] adb devices returned 0
    $ /opt/android/android-sdk-20-linux_x86/platform-tools/adb -s emulator-5607 shell getprop dev.bootcomplete
    error: device offline