Added possibility to return tuple from filterfunc

If the returned type is a tuple, it will be interpreted as first the
title (i.e. hovertext), then the content of the infowindow. If the
returned type is a string, it will be used as both the title and
infowindow content (the old behaviour). This means that older configs
are still compatible and need no changes.
specifying a directory name for a dimension should work now
updated tileset.py and genPOI.py and a few other stragglers
Add support for Quartz ore and redstone block

See #863
First pass an rendering comparators

See #863
Add less verbose config option
Load textures from the new textures folder (intead of terrain.png)

See #863
Handle HD textures and animated textures
Weighted pressure plates

See #863
Support for the Daylight sensor

See #863
updaded doc download links
Merge in pull request #865
Merge Pull Request #859
Allow unicode to be returned from a genPOI filter function
Updated documentation

* Added paragraph and example about returning tuples from a filter
  (Issue #859)

* Added section about manualpois
  (Issue #858, Issue #869, Issue #598)

* Fixed a typo in the FAQ

* Added logging to file to the FAQ
  (Issue #871)
use git to find current hash, should work with overviewer-as-submodule
JSObserver will show ETA, and the 'renderComplete' message will persist

Closes #784
Closes #786
Merge in pull request #872
Merge pull request #862
Make sure that regionset.type always has a value