v4.0.0

Changelog

Implemented enhancements:

• Support bignumber.js@7+ and add optional validateSignificantDigits flag #174 (ricardobcl)

Merged pull requests:

• Update google-libphonenumber #173 (rplopes)
• Fix mixed content issue preventing page load #170 (hitmanmcc)
• Update ownership #169 (ruimarinho)
• Update README to include new asserts #165 (kurayama)