otasigcheck and backuptools from CM

Change-Id: I1b582d57ed58176db83ec046e68884cd9e4a1b6a

Add otasigcheck.sh from cm

Change-Id: I930b06ccd1d8fc2b10bdb5e98418efb05ca28e71
diff --git a/prebuilt/common/bin/backuptool.functions b/prebuilt/common/bin/backuptool.functions
index 833460f..10d66a4 100644
--- a/prebuilt/common/bin/backuptool.functions
+++ b/prebuilt/common/bin/backuptool.functions
@@ -5,7 +5,7 @@
 
 export C=/tmp/backupdir
 export S=/system
-export V=9
+export V=12
 
 backup_file() {
   if [ -e "$1" ]; then