Function convertLength

convertLength(length, toUnit, fromUnit?): number
JMap.Geometry.convertLength

Converts the distance from a unit to another.
Parameters
- length: number
  the distance to convert
- toUnit: JMAP_DISTANCE_UNITS
  the output unit
- Optional fromUnit: JMAP_DISTANCE_UNITS
  the input unit
Returns number
Throws
if invalid parameters

Example
```
// returns 2 kilometers in miles
JMap.Geometry.convertLength(2, "miles")

// returns 200 meters in yards
JMap.Geometry.convertLength(200, "yards", "meters")
```