POI dict and polyline support

Added support for filter functions to return dicts.
Added support for filter functions to return a list of coordinates to
draw lines between when shown.
Merge branch 'master' into POI-Polylines
Add option to skip scanning for POIs in regions

Sometimes, people just use --genpoi for manual POIs. This option
allows them to save some time by not handling entities.
Merge pull request #908 from CounterPillow/genpoi-skipscan

Add option to skip scanning for POIs in regions
overviewer now pulls fire/lava/water textures from the right place

fixes issue #910
Added some debug stuff

Hopefully this will be useful in tracking down dimension/rendermode
issues
Docs adjustment: 0.9 is no longer "new"

We should really remove or clean up the features section. Maybe make a
new "changelog" page. Although that's probably not a good idea because
we'd probably just forget to update it.
added faq entry about erroneous chunks causing blank maps

This seems to come up often enough to warrent an FAQ entry. Wrote up an
explanation of what happen and what to do.
bumped docs version number.

we always forget to bump the version in the docs
Lilypads are now properly oriented.
Add section about importing in the config file

Add a section that describes how users can import parts of their config from other files.
nbt timestamps are probably signed (like time_t)

Besides, we get overflow errors with utime on windows for large
unsigned 32-bit integers.
Docs updates for #882 (JSObserver formatting strings)
Added: Hay blocks, Hardened Clay, Coal blocks, and Carpet.
Added stained hardened clay
Add all stem and all cap blocks for big mushrooms.
added support for hashchange event for recent browsers
hashchange triggered by setHash is now properly ignored
Changed default poititle to "Markers"

I feel this is more accurate and it has been bugging me for a
while now.
Added option showlocationmarker