pastebuf.lua 0.2: new supported sites, new options, bugs fixed

Changes:
- More supported sites: codepad.org, fpaste.org, ideone.com,
  pastebin.osuosl.org, and vpaste.net.
- Script now has optional dependency, lua-cjson. This is used for:
    - support of multiple files in a gist
    - detect language used in the pastes from gist.github.com, fpaste.org,
      and pastebin.osuosl.org.
- Add 'special' commands inside paste buffer (see /help pastebuf).
- For sprunge.us and vpaste.net, detect language of paste from the query
  string (if there's any).
- Add parameter `**open-recent-url` to tell script to search for any
  recent paste URLs inside current buffer and open them.
  The maximum number of URLs the script should search can be specified in
  the second parameter. If it's not specified, script will only search for
  1 recent URL.
- Fix CSI SGR parsing.
- Change the default fetch_timeout from 5 seconds to 30 seconds. Some
  sites are really slow.
- Add show_line_number option to toggle the display of line number.
autoauth.py 0.10: fix "/auth cmd" command line parsing
weetext.py 0.1.2: add hook_timer to make sure wtrecv.py is running
New script autosort.py: automatically keep buffers grouped by server and sorted by name
Merge branch 'master' of git://git.sv.gnu.org/weechat/scripts