2. Fix a bug in handling the overlapped case by reverse-copying the destine region & source region
3. Fix an issue that the leading spaces could not be displayed in highlight mode
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@2410 6f19259b-4bc3-4df7-8a09-765794883524