BaseRepositoryBuilder should trim CR from .git symref

Change-Id: I909c2892100da89f6670ffbf3442f11c9cb7b008
Signed-off-by: Marc Strapetz <marc.strapetz@syntevo.com>

org.eclipse.jgit/src/org/eclipse/jgit/lib/BaseRepositoryBuilder.java

@@ -109,7 +109,8 @@ public class BaseRepositoryBuilder<B extends BaseRepositoryBuilder, R extends Re
 
 		int pathStart = 8;
 		int lineEnd = RawParseUtils.nextLF(content, pathStart);
-		if (content[lineEnd - 1] == '\n')
+		while (content[lineEnd - 1] == '\n' ||
+		       (content[lineEnd - 1] == '\r' && SystemReader.getInstance().isWindows()))
 			lineEnd--;
 		if (lineEnd == pathStart)
 			throw new IOException(MessageFormat.format(