encode_waypoints output differs by Python version

[perrygeo]

The implementation relies on the behavior of round which differs between python 2.7 and 3.x

from mapbox.encoding import encode_waypoints

features = [{
  "type": "Feature",
  "geometry": {
    "type": "Point",
    "coordinates": [1, 0]
  },
  "properties": {}}]

print(encode_waypoints(features))

gives us

• 1,0 for Python 3
• 1.0,0.0 for Python 2

This should not affect the value returned from the Mapbox SDK but it means that the precise URL is not deterministic - which might affect caching and tests.

[perrygeo]

@critical-path FYI this was the bug causing the directions CLI tests to fail on python 2.7 in mapbox/mapbox-cli-py#122. I'm going to account for it on the CLI side