Document, in particular use of UTF-8. Simplify code in a couple of

places, but no functional changes.

src/lib/player/dispatch.c

@@ -48,10 +48,9 @@
 
 /*
  * Execute command named by player->argp[0].
- * BUF is the raw command line (user text).  It should have been
- * passed to parse() to set up player->argp.
- * If REDIR is not null, it's the command's redirection; it is user
- * text.
+ * BUF is the raw UTF-8 command line.  It should have been passed to
+ * parse() to set up player->argp.
+ * If REDIR is not null, it's the command's redirection, in UTF-8.
  * Return -1 if the command is not unique or doesn't exist, else 0.
  */
 int