workspace.c: update header, reformat

src/workspace.c

@@ -1,11 +1,8 @@
 /*
- * vim:ts=8:expandtab
+ * vim:ts=4:sw=4:expandtab
  *
  * i3 - an improved dynamic tiling window manager
- *
- * © 2009-2010 Michael Stapelberg and contributors
- *
- * See file LICENSE for license information.
+ * © 2009-2010 Michael Stapelberg and contributors (see also: LICENSE)
  *
  * workspace.c: Functions for modifying workspaces
  *
@@ -14,8 +11,6 @@
 
 #include "all.h"
 
-extern Con *focused;
-
 /*
  * Returns a pointer to the workspace with the given number (starting at 0),
  * creating the workspace if necessary (by allocating the necessary amount of