Strip leading slashes in RepositoryFilter

If removing the leading slash results in an empty string, return
with an HTTP 404 error before trying to use the RepositoryResolver.
Moving this into a loop ahead of the length check ensures there is
no empty string passed into the resolver.

Change-Id: I80e5b7cf25ae9f2164b5c396a29773e5c7d7286e

org.eclipse.jgit.http.server/src/org/eclipse/jgit/http/server/RepositoryFilter.java

@@ -122,12 +122,12 @@ public class RepositoryFilter implements Filter {
 		final HttpServletRequest req = (HttpServletRequest) request;
 
 		String name = req.getPathInfo();
+		while (name != null && 0 < name.length() && name.charAt(0) == '/')
+			name = name.substring(1);
 		if (name == null || name.length() == 0) {
 			((HttpServletResponse) rsp).sendError(SC_NOT_FOUND);
 			return;
 		}
-		if (name.startsWith("/"))
-			name = name.substring(1);
 
 		final Repository db;
 		try {