Make the cursor shapes more descriptive.

»IBeam« is now »Bar« because it's named like that in the source code.

config.def.h

@@ -108,10 +108,10 @@ static unsigned int defaultrcs = 257;
 
 /*
  * Default shape of cursor
- * 2: Block
+ * 2: Block ("█")
- * 4: Underline
+ * 4: Underline ("_")
- * 6: IBeam
+ * 6: Bar ("|")
- * 7: Snowman
+ * 7: Snowman ("☃")
  */
 static unsigned int cursorshape = 2;