Add valgrind tests and fix memleaks

mfapi/apicalls/user_get_info.c

@@ -19,6 +19,7 @@
 
 #include <jansson.h>
 #include <stdio.h>
+#include <stdlib.h>
 
 #include "../../utils/http.h"
 #include "../../utils/json.h"
@@ -45,6 +46,8 @@ int mfconn_api_user_get_info(mfconn * conn)
     retval = http_get_buf(http, api_call, _decode_user_get_info, NULL);
     http_destroy(http);
 
+    free(api_call);
+
     return retval;
 }