Code review comment for lp:~mardy/click/lp1245826

This looks basically good, and at least I'm fine with the changes to the hooks specification; thanks, and sorry for the delay on this.

However, the implementation will need to be ported to libclick. I also suspect that the handling of removals isn't right - it looks to me as though any hooks whose patterns include ${basename} won't have their symlinks properly removed. We can probably deal with this using the possible_expansion logic.

Given how long I've kept you waiting, I think it's sensible for me to just merge this into libclick myself and figure out tests sufficient to exercise my suspicion above. I'll try to get this done today.