Clarify docstring for meow-visit #431 (#433)

Default behavior now is you either select one candidate (word or
symbol in buffer), or search for raw string. The regexp quote will
prevent it to be treated as regexp. Docstring should not give an
impression that `meow-visit` searches for regexps.

The dual function of `meow-visit-sanitize-completion` is also
explained in better detail.

Author: akho

meow-command.el

@@ -1344,14 +1344,15 @@ Argument REVERSE if selection is reversed."
           (funcall func-2 text nil t 1)))))
 
 (defun meow-visit (arg)
-  "Read a regexp from minibuffer, then search and select it.
+  "Read a string from minibuffer, then find and select it.
 
 The input will be pushed into `regexp-search-ring'.  So
 \\[meow-search] can be used for further searching with the same condition.
 
-A list of occurred regexps will be provided for completion, the regexps will
-be sanitized by default. To display them in raw format, set
-`meow-visit-sanitize-completion' to nil.
+A list of words and symbols in the current buffer will be provided for completion.
+To search for regexp instead, set `meow-visit-sanitize-completion' to nil.
+In that case, completions will be provided in regexp form, but also covering
+the words and symbols in the current buffer.
 
 To search backward, use \\[negative-argument]."
   (interactive "P")