Add basic error checking to legacy property init

Let init and rename funcitons return success or failure values.

Change-Id: Ieed86cac8a0dcfd770a89dacc57fd306e7a6ad8d
Allow disabling legacy properties

Introduce TW_NO_LEGACY_PROPS flag for users that build TWRP in
non-kitkat trees and don't need the legacy prop environment.

Change-Id: Iacb2d9af7d7069acb3d0a96bb34f32ded6317a20
Cleanup DU Get_Folder_Size function

Change-Id: I3c686c7c3a171f130d299fae586dc811cad0d3a9
Fix /data backup size if contains media subdirs

/data/*/media directories are mistakenly being excluded from the size
calculation. Change to absolute dir exclude so that only /data/media is
excluded.

Change-Id: I6e97604d44e6ea2bdf7dfd8c68a2f90ba6d44415
Actually skip excluded files from tar backup

Change-Id: Ibbc4eb2eb89863ccb2a15f5a3b5092fb10fcbcc0
correctly mount tmpfs as /tmp in recovery

The syntax of init's mount command changed in April 2008 but
recovery's init.rc was never updated, so recovery's /tmp has been on
the root fs all this time.  Fix.

Also add /system/bin to the PATH in recovery, which is handy for
debugging.

Change-Id: I9e60d18803906bc75c263f12c8863cfd6a14147b
Squashed USB PID update for adb and adb+ums modes

These were commited in CWM to help Windows differentiate between adb and
adb+ums USB modes.
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use different USB PIDs for adb and adb+ums modes

Commit ad054c684524962eae3269c1d807dc60e8bca1ec made it so that
the same VID/PID pair was used for both adb and composite adb+ums
modes, which prevents the installation of drivers in Windows so that
either mode can be supported.

This uses the original VID/PID pair (18d1/d001) for adb+ums and
uses 18d1/d002 for adb.
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use correct USB PID for adb and new PID for adb+ums

The previous commit assumed that the correct PID for adb+ums
was 18d1/d001. That is incorrect. That VID/PID pair is widely
used for non-composite adb function in recovery. Since there is
no "generic Android" VID/PID allocated for adb+ums, we will
"unofficially reserve" an unused one for that purpose: 18d1/d003.

Change-Id: I889c40939fc51e58478d379812d90869923ed595
Add HTC charging LED support

Original implementation by Tom Hite, only slightly modified by Matt
Mower.

Change-Id: Ibc73bf04f122f5de1702f8beeccc468a9a1a2e95