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 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.
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
removed bit about __init__.py
Merge branches 'config-include', 'hashchange', 'poi-polylines', 'showlocationmarker' and 'signed-timestamps'
updated contributors list