Minor consistency fixes for the copyright header and update the tables to current. PX4Buildbot will periodically update the tables automatically from this point.
- updated table to 2 bytes (int16) per element and scaled the inclination/declination/strength tables to use most of the range without being too awkward
- tables have been extended to include the full latitude range
- expanded the API slightly to offer declination/inclination in both degrees/radians and the magnetic strength in Gauss and Tesla
- generated some simple testing that verifies interpolation between points
