open.vim: Bug fix for error handling code (the "not implemented" message)
xolox#misc#open#file(): Improve documentation & variable names
xolox#misc#open#file(): Instrument with xolox#misc#msg#debug() calls
Properly detect Mac OS X using xolox#misc#os#is_mac()

Related to vim-shell issue #18:
  https://github.com/xolox/vim-shell/issues/18
Bug fix for xolox#misc#open#url() on Mac OS X (xolox/vim-shell#18)

Related to vim-shell issue #18:
  https://github.com/xolox/vim-shell/issues/18
Version string parsing and comparison functions
Updates required by vim-notes 0.22
Bump version (it's late)
xolox#misc#os#exec(): Improve error reporting about temporary files

See issue xolox/vim-easytags#58:
  https://github.com/xolox/vim-easytags/issues/58