Add multiple decoration, fix interim title change
Add multiple decoration, fix interim title change

Add support for having multiple Hooker decorators per function. This is
especially useful for WM hooks, that might want to use the same runner for
multiple events.

Extend hlwm hook to have support for multiple decorations.

Add window_title_changed event to windowtitle changer, effectively making the
windowtitle value update on tab changes in your browser or when you switch
buffers in vim.

thiderman/storm