Daniel Convissor wants to test ext/date/lib, so enable code coverage data for him

Makefile.gcov

@@ -61,7 +61,7 @@ php_lcov.info: lcov-test
 		test -f "$$x.bb"   && cp $$x.bb   lcov_data/$$y.bb ; \
 		test -f "$$x.bbg"  && cp $$x.bbg  lcov_data/$$y.bbg ; \
 	done
-	for dir in ext/bcmath/libbcmath ext/date/lib ext/fileinfo/libmagic ext/gd/libgd ext/mbstring/libmbfl ext/mbstring/oniguruma ext/pcre/pcrelib ext/pdo_sqlite/libsqlite ext/sqlite/libsqlite ext/sqlite3/libsqlite ext/xmlrpc/libxmlrpc ext/zip/lib; do \
+	for dir in ext/bcmath/libbcmath ext/fileinfo/libmagic ext/gd/libgd ext/mbstring/libmbfl ext/mbstring/oniguruma ext/pcre/pcrelib ext/pdo_sqlite/libsqlite ext/sqlite/libsqlite ext/sqlite3/libsqlite ext/xmlrpc/libxmlrpc ext/zip/lib; do \
 		test -d lcov_data/$$dir && rm -rf lcov_data/$$dir ; \
 	done
 	@echo