v4.0.0

This Release introduces some more optimizations both in size of bundles,
memory usage and speed of parsing. Because it introduces some breaking
changes in the API results (host renamed into hostname and deletion
of the isValid attribute), as well as introducing a new experimental
backend (tldts-experimental bundle), this is a major version bump.

• #16 Optimizations + comparison with other libraries (#16)

  • Optimize Trie into a DAWG (size reduction)
  • Implement comparison with other libraries
  • Implement fast path for valid hostnames as arguments
  • Allow to disable hostname parsing and validation using option
  • Add tests for corner-cases URLs parsing
  • Update README

• #13 Implement experimental probabilistic packed suffix structure (#13)

  • Implement packed hash probabilistic structure for more compact
    representation and faster lookups. See ./bin/builders/hashes.js for more
    details about how it works.
  • Create second bundle (tldts-experimental) making use of this new implementation
  • Simplify hostname validation and remove strict IDNA checks
  • Move lookup implementations into 'lookup' sub-folder
  • Move compiled data into 'lookup/data' sub-folder
  • Refactor suffix list parsing out of builders
  • Handle IDNA hostnames at build-time instead of runtime (by indexing
    some suffixes multiple times: once puny-coded and once in unicode form)