Load map file in non-strict mode

[mdholloway]

Needed to avoid errors with fonts.

Bug: https://phabricator.wikimedia.org/T195513

[thesocialdev]

Tests are failing locally, in master there are 27 fails and in your branch 28 fails, I am not sure what it can be but I think we should double check.

[mdholloway]

Most of the failures are due to the requirement to set a MapboxAccessToken environment variable with an API token from Mapbox before running the tests. This seems to be a new requirement since the tests were written. (Actually, it's also an open issue upstream: mapbox#153)

When I view my Mapbox account, it has a default public token that I think was auto-created when I created the account. Setting it as the value of the MapboxAccessToken env var got these tests passing. (Hopefully I won't be charged, still need to check...)

There are a couple of other tests failing due to an Amazon s3 auth failure somewhere, and these can be quieted by setting TILELIVE_VECTOR_NO_AUTH (see mapbox#116).

With these environment variables set, all tests pass for me both before and after this change. Can you verify?