Add some compile infos for mac users.
Fix static link options for libboost_program_options
Remove generator setting from Writer class.

We use the setting in Header instead. This is more consistent with the rest of
the settings in Header.
Remove mentioning of the unused THREAD parameter.
Make NodeLocationsForWays handler easier to use.

Provides a default dummy index for negative IDs, because they are almost never
needed.
Provide haversine functions.