Set up codeclimate for static analysis + test coverage

[zspencer]

Resolves #20

This also turns on "rails" mode for Coveralls, which maybe we don't want to do? I was just getting nervous seeing that 100% covered despite knowing we've got uncovered stuff.

It appears codeclimate's coverage is incompatible with coveralls, but that's fine since coveralls notifies us when the number drops below a certain amount. It does mean we won't get to see the unified maintainability / coverage view in CodeClimate, but that's ok.

[coveralls]

Coverage remained the same at 100.0% when pulling d595490fda2f311eb3b9547f206ee2e5fc6e179e on zs-hook-in-codeclimate into 927781e13855f3eb5cd2bb9b6b6f4c30d05fa11d on primary.

[coveralls]

Coverage remained the same at 100.0% when pulling 64ac62e9d16bb33121267e5b435299e68c2c0cda on zs-hook-in-codeclimate into 927781e13855f3eb5cd2bb9b6b6f4c30d05fa11d on primary.

[coveralls]

Coverage remained the same at 100.0% when pulling aad76861d75cf3c3f022a12918cb87be6a1ba1d1 on zs-hook-in-codeclimate into 927781e13855f3eb5cd2bb9b6b6f4c30d05fa11d on primary.

[coveralls]

Coverage decreased (-65.5%) to 34.483% when pulling 98aca1d0a3b0076f1f09e3c8921f335919a54945 on zs-hook-in-codeclimate into 927781e13855f3eb5cd2bb9b6b6f4c30d05fa11d on primary.

[coveralls]

Coverage decreased (-65.5%) to 34.483% when pulling b5952e009d7e41c4264cb516f13b72134957043d on zs-hook-in-codeclimate into 927781e13855f3eb5cd2bb9b6b6f4c30d05fa11d on primary.

[coveralls]

Coverage decreased (-65.5%) to 34.483% when pulling ba409fdb54d7177872f34c63c536c3e70efd9605 on zs-hook-in-codeclimate into 927781e13855f3eb5cd2bb9b6b6f4c30d05fa11d on primary.

[bhaibel]

I think we don't need both Coveralls and CodeClimate for coverage reporting and should pick one. I'm leaning slightly towards Coveralls because its reports seem more granular, but don't have strong feelings.

[zspencer]

Yep, I agree. Was hoping I could make it work with both but since it took more than 30m I'm going to remove that and rebase it down to one.

[coveralls]

Coverage decreased (-65.5%) to 34.483% when pulling a85fb1a327a8f357f7c6da9ca734953f5b85568a on zs-hook-in-codeclimate into 927781e13855f3eb5cd2bb9b6b6f4c30d05fa11d on primary.

[coveralls]

Coverage decreased (-65.5%) to 34.483% when pulling a85fb1a327a8f357f7c6da9ca734953f5b85568a on zs-hook-in-codeclimate into 927781e13855f3eb5cd2bb9b6b6f4c30d05fa11d on primary.