mappings: restore "q" mapping, soft-deprecate "gq"

Essentially reverts cfc66aa.

- `q` is much more ergonomic than `gq`.
- `q` continues to win in the wild, and is used for e.g. quitting
  a `:Man` buffer.
- "quit" is a vastly more-common use-case than "record a macro".
- One can use a mapping like `\q` to opt-in to macro recording when it
  is needed.

Author: justinmk

doc/dirvish.txt

@@ -48,7 +48,8 @@ Buffer-local (filetype=dirvish) ~
                     Sets |g:dirvish_mode| to [count], if given.
                     Mnemonic: higher [count] => more files.
     <Plug>(dirvish_quit)
-    gq              Quits and returns to the original file.
+    q               Quits and returns to the original file.
+    gq              Alias to "q". May be removed in the future.
     <2-LeftMouse>
     i
     <CR>            Opens file at cursor.

ftplugin/dirvish.vim

@@ -7,6 +7,7 @@ let s:nowait = (v:version > 703 ? '<nowait>' : '')
 let s:sep = exists('+shellslash') && !&shellslash ? '\' : '/'
 
 if !hasmapto('<Plug>(dirvish_quit)', 'n')
+  execute 'nmap '.s:nowait.'<buffer> q <Plug>(dirvish_quit)'
   execute 'nmap '.s:nowait.'<buffer> gq <Plug>(dirvish_quit)'
 endif
 if !hasmapto('<Plug>(dirvish_arg)', 'n')