v1.0

• Major changes (see #24):
  • Switch to swagger2-2.*;
  • Add automatic ToJSON/ToSchema validation tests;
  • Add great documentation;
  • Export some type-level functions for servant API.
• Minor changes:
  • Rework Todo API example;
  • Stop exporting ToResponseHeader, AllAccept and AllToResponseHeader (see bd50db4);
  • Change maintainer, update authors/copyrights (see 1a62681);
  • Include changelog and example files into extra-source-files.