MGRS utility for Proj4js

[ahocevar]

MGRS is a reference system that uses strings to encode UTM coordinates to a grid with 1, 10, 100, 1000 or 10000 m accuracy. While not to be seen as a projection that could be added to Proj4js with a projection definition, this would still make sense as an utility.

[ahocevar]

MGRS utility

[ahocevar]

The above patch adds a Proj4js.util namespace with a MGRS utility. This utility also works standalone, but if used with Proj4js, it will add a fromMGRS function and a toMGRS method to Proj4js.Point.

A forward-only version of this utility was part of Community Mapbuilder, and the routines used in this utility are ported from the com.bbn.openmap.proj.coords Java package of OpenMap?.

[madair]

Added. I will leave this out of the single file build for now. Devs can add it to their own build by including it in the build/library.cfg file, or just include the JS file.

Thanks Andreas for adding this.