doc: add developing and testing info to backup guide
doc: add developing and testing info to backup guide

Change-Id: I1e9c9f412033ecf517ea566ce70686f42e7c568e

xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base