Merge branch 'feature/header-config' into 3.1

Merge branch 'fix-typ-header' into 3.0

Changing Travis to just allow failures in HHVM-nightly and disabling …

…some environment services in Scrutinizer.

Adding type cast to ValidationData (fixes lcobucci#28)

Merge pull request lcobucci#26 from lcobucci/fix-token-parsing

Delegating payload generation to Builder and Parser

fixed hmac verify

Upgrading dependencies.

Security fixes and new small features

Version 2.1.1

- Typo fixed (lcobucci#20)

Version 2.1.0 relased!

New features:

- RSA signers
- ECDSA signers
- Token::getClaim() method

Improved readme