Use ro.cm.display.version when reporting

People are getting confused because their CM version listed on their
CMAccount says "SNAPSHOT" when they are running an installer build.
They are asking why they are not running stable builds, however, the
installer snapshot builds are built off the stable branch.

Display version is more appropriate here.

Change-Id: Iad33e3ee5098c146fd77ccf06a708c4eec57b96d
Merge branch 'cm-11.0' of https://github.com/CyanogenMod/android_packages_apps_CMAccount into cd-4.4