Remove hacky helper code, add tests for build_url
Remove integration tests

These have been moved to a standalone project: microcosm-cc/microweb-integration
Parameterise build_url to use API scheme, version
Add support for multiple sites

This adds support for multiple sites by using the current request's Host to construct the backend service URL for each API call
Remove selenium requirement, add mock dependency
Test that request host is used to call construct API url

For all resources, the request host must be used to call the backend.

This test patches requests.get and verifies the correct API url is being called.
Merge pull request #50 from mattcottingham/master

Add support for multiple subdomains on microco.sm