Add new nether render mode.
Added name to CONTRIBUTORS.rst
Added Entities support
Fix crop validator to avoid trying to alter a tuple
Add option to configure maxzoom and appropriate documentation
Merge commit 'refs/pull/817/head' of github.com:overviewer/Minecraft-Overviewer into merge_817
Merge commit 'refs/pull/815/head' of github.com:overviewer/Minecraft-Overviewer into merge_815
Renamed the current nether to netherold, and made the new nether2 the default
Add png-it.py script to contrib directory

Creates 1 big PNG images from an overviewer tileset directory

Addresses #826
Added marker at coordinates in the url

Addresses issue #782
Changed location marker icon and animation
Fix partial traceback printing on Windows
Merge commit 'refs/pull/847/head' of github.com:overviewer/Minecraft-Overviewer into merge_847
Merge branch 'master' of git://github.com/overviewer/Minecraft-Overviewer

Conflicts:
	overviewer_core/data/js_src/overviewer.js
Add nether brick slab support
Added manual POI option

Here's how to use it:
have a list called "manualpois" in your config filled with objects that contain
the attributes id, x, y and z. Feel free to add more attributes as you need them.
Then, write filter functions to filter for your custom POIs (hint: use the id).
manualpois is now a per-render option
Merge branch 'master' of git://github.com/overviewer/Minecraft-Overviewer
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.
Don't print scary traceback when textures cannot be found

See #860