[GraphHopper] Looking for an engine for horse (and hiking) routing

[Peter K]

>>> feel free to optimize whereever you can - I appreciate every
>>> improvement! The parser could be improved in many areas e.g. adapted so
>>> that the protobuf protocol is supported (this would be faster IMO).
>> That might be a little faster, but I have something else in mind. I
>> spotted some unneccessary operations, but there is a fast way to skip
>> over all of the nodes in the 2-pass Reader and immediately parse the
>> ways. For large files this is much faster than parsing and ingoring
>> them, but it only works in uncompressed osm xml.
> Ah, ok. Also putting parsing and storing the edges into two threads (+ a
> queue) could speed things up.

BTW: if you don't have a large area or enough RAM (or both ;)) then you
can avoid double parsing the xml, but this would need another subclass
of OSMReaderHelper. There was one before but the advantage was not that
big and I had to maintain two things, so I removed it:
* f76e2a2 2013-02-10 | remove OSMReaderHelperSingleParse [Peter]