Enums.GridType enumeration

The GridType can be one of:

Constant	Description
`Enums.GridTypeUnknown`	`(-1)` Unknown grid type.
`Enums.GridTypeLatitudeLongitudeGrid`	`(0)` LatitudeLongitudeGrid - Latitude and longitude (graticules).
`Enums.GridTypeUTMGrid`	`(1)` UTMGrid - Universal Transverse Mercator (UTM).
`Enums.GridTypeMGRSGrid`	`(2)` MGRSGrid - Military Grid Reference System (MGRS).
`Enums.GridTypeUSNGGrid`	`(3)` USNGGrid - United States National Grid (USNG).