Reported by github.com/joelmats. The array passed to
Geocoder::Calculations.geographic_center was being modified in-place.

Multiply by .707 (sin(45)) instead of .5.

Get rid of space after comma, if any (Google was returning no results).

Just for interface consistency across database types. NOT for accuracy!

Was ignoring non-ASCII characters. Thanks to github.com/supergivi for
reporting the bug.

Response to Issue #27, posted by github.com/avioing.

Also clean up code comments.

This allows easier substitution of custom values.

This was yielding incorrect bearing calculations (east and west were
treated as the same direction).

Only worked with MySQL.