Change the kilometer cutoff on stringFromDistance:

Previous was  if (kilometerDistance > 1) but if it's 1000m I don't want to see 1000m but 1km.

Signed-off-by: Luca Bernardi <luka.bernardi@gmail.com>
Add distanceStyle for change the style of distance unit

allows you to specify the style to be used for the distance unit.

`TTTDistanceWordStyle` prints the unit with is name (e.g. "kilometer") and support the singular e plural.

`TTTDistanceAbbreviationWordStyle` prints the unit with its symbol (e.g. "km")

This change is provided with an example.

Signed-off-by: Luca Bernardi <luka.bernardi@gmail.com>