collect_dir() will now pre-load all files and return a function that will
collect all information.

Apart from replacing a patch for the former by two patches for latter,
this involved minimal adaptations of the lua scripts in the following
packages:

* gluon-announce
* gluon-announced
* gluon-mesh-batman-adv-core
* gluon-status-page

This also adds an extended query protocol and deflate compression.