Support of multiple layouts has been added.

The command /layout now supports a name for actions save/apply/reset.

New options have been added:

• leave: leave current layout (it will not update any layout)
• rename: rename a layout

The output of /layout has been improved, especially the tree of windows:

Saved layouts:
  mobile:
    1. core.weechat
    1. irc.server.local
    2. irc.local.#test
    3. irc.local.#test2
  desktop (current layout):
    1. core.weechat
    1. irc.server.local
    2. irc.local.#test
    3. irc.local.#test2
    \== 40% (splith)
      |-- irc.local.#test
      |== 50% (splitv)
        |-- irc.server.local
        |-- irc.local.#test2