Fix Subversion keyword collapsing to not break with unterminated keywords.
Review Request #469 - Created March 14, 2017 and updated
If an unterminated keyword (such as "$Id:" instead of "$Id$" or "$Id:$") appeared in a file being patched, it would result in a breakage during patch. We now assume this is not a keyword if it contains a newline. Patch by Masakazu Hamaji Fixes bug #1523