add CS_ERR_VERSION to report error when binding version is different from core's API version
diff --git a/cs.c b/cs.c
index 46a89e4..e6e4434 100644
--- a/cs.c
+++ b/cs.c
@@ -117,6 +117,8 @@
 			return "Details are unavailable (CS_ERR_DETAIL)";
 		case CS_ERR_MEMSETUP:
 			return "Dynamic memory management uninitialized (CS_ERR_MEMSETUP)";
+		case CS_ERR_VERSION:
+			return "Different API version between core & binding (CS_ERR_VERSION)";
 	}
 }