updated for version 7.4.275

Problem:    When changing the type of a sign that hasn't been placed ther is
            no error message.
Solution:   Add an error message. (Christian Brabandt)

src/version.c

@@ -734,6 +734,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    275,
 /**/
     274,
 /**/