adb: Look for bu in /sbin when in recovery mode

 * Restore global variable recovery_mode.  This is set based on the
   commandline parameter --banner.

 * Use recovery_mode to select path to 'bu' binary for both backup and
   restore services.

Change-Id: Ie4c945d00601514d7f16357bae10ff7f232633e1
 healthd: increase healthd fast timer to 10mins instead of 1min

healthd 1 min wakeups are causing significant power impact
during static display use case. so increasing the timer to 10min.

Change-Id: If7a514e4152789144242e198175918b6687c3bcf
adb: Fix compilation warning

Change-Id: Iab0cb977f81824338a37ecba233b45883c0bc13b
adb: Allow configuring the adb shell with a persistent property.

To set to bash: setprop persist.sys.adb.shell /system/xbin/bash

Change-Id: I24e65f4592aaf23356c13db02c9869076df3b841
Merge branch 'cm-12.0' of https://github.com/CyanogenMod/android_system_core into lp5.0