Merge pull request #59: Make :RestartVim retain server name

See pull request #59 on GitHub:
  https://github.com/xolox/vim-session/pull/59
Bug fix: Disable Vim's special handling of initial, empty buffer

See issue #28 on GitHub:
  https://github.com/xolox/vim-session/issues/28
Internal refactoring: Merge s:get_name() and xolox#session#find_current_session()
Internal refactoring: Replace s:select_name() with xolox#session#prompt_for_name()
Working on inline function documentation
More inline function documentation :-)
Bug fix: Re-implement Vim's special handling of initial, empty buffer

See issue #60 on GitHub:
  https://github.com/xolox/vim-session/issues/60

This is a follow up to my recent changes for issue #28:

  Bug fix: Disable Vim's special handling of initial, empty buffer
  https://github.com/xolox/vim-session/issues/28
Make sure vim-misc is installed, politely complain if it isn't

See issue #65 on GitHub and numerous other issues before it:
  https://github.com/xolox/vim-session/issues/65
Add session_default_overwrite option (see readme for details)

See also issue #62 on GitHub:
  https://github.com/xolox/vim-session/issues/62
Support for sessions with multiple TagList windows

See issue #66 on GitHub:
  https://github.com/xolox/vim-session/issues/66
Allow to turn off the default Session menu via g:session_menu config flag.

I find it annoying that the plugin installs itself into a highly visible top-level menu, and the provided commands are quite symmetrical and easy to remember.
Merge pull request #70: Allow to turn off Sessions menu

See pull request #70 on GitHub:
  https://github.com/xolox/vim-session/pull/70
Merge remote-tracking branch 'origin/master' into ServerNameRestartFix