Update README.rst
Whitelist external entities for HHVM/libxml.

Refs: facebook/hhvm@842d6fb
Merge pull request #423 from whatthejeff/hhvm-libxml-regression

Whitelist external entities for HHVM/libxml.
Switching to Behat3
Added default formatter, fixed spacing, removed redundant line
Moving tag filter to global, so that it can be overriden at CLI
Fugbix typo.
Merge pull request #425 from whatthejeff/patch-3

Fugbix typo.
Add missing matcher features.
Add missing matcher documentation.
Merge pull request #426 from whatthejeff/document-matchers

Improve matchers documentation.
Merge pull request #424 from ciaranmcnulty/behat3

Upgrade Behat to v3
Removing Generators from scrutiny
Merge pull request #427 from ciaranmcnulty/config-scrutinizer-fatals

Removing Generators from scrutiny