Added automatic version distinguishing code, to differentiate releases

from nightly builds from random development builds

[originally from svn r28]

putty.h

@@ -226,6 +226,11 @@ void *safemalloc(size_t);
 void *saferealloc(void *, size_t);
 void safefree(void *);
 
+/*
+ * Exports from version.c.
+ */
+extern char ver[];
+
 /*
  * A debug system.
  */