Added new define for schema literal

Author: marcobambini

src/cloudsync.c

@@ -1544,7 +1544,7 @@ void cloudsync_sync_key (cloudsync_context *data, const char *key, const char *v
         return;
     }
 
-    if (strcmp(key, "schema") == 0) {
+    if (strcmp(key, CLOUDSYNC_KEY_SCHEMA) == 0) {
         cloudsync_set_schema(data, value);
         return;
     }

src/dbutils.h

@@ -22,6 +22,7 @@
 #define CLOUDSYNC_KEY_CHECK_SEQ             "check_seq"
 #define CLOUDSYNC_KEY_SEND_DBVERSION        "send_dbversion"
 #define CLOUDSYNC_KEY_SEND_SEQ              "send_seq"
+#define CLOUDSYNC_KEY_SCHEMA                "schema"
 #define CLOUDSYNC_KEY_DEBUG                 "debug"
 #define CLOUDSYNC_KEY_ALGO                  "algo"