new context_info struct in compat checks (trunk only)

Add the context_info struct to the version compatibility checks.
This increments EDITLEVEL rendering prior save/bones files useless.

include/global.h

@@ -301,7 +301,8 @@ struct version_info {
 	unsigned long	incarnation;	/* actual version number */
 	unsigned long	feature_set;	/* bitmask of config settings */
 	unsigned long	entity_count;	/* # of monsters and objects */
-	unsigned long	struct_sizes;	/* size of key structs */
+	unsigned long	struct_sizes1;	/* size of key structs */
+	unsigned long	struct_sizes2;	/* size of more key structs */
 };