Add travis build on PHP 5.5, allow failure
Build libevent extension instead of using pecl
Merge remote-tracking branch 'romainneutron/travis-php-5.5'

* romainneutron/travis-php-5.5:
  Build libevent extension instead of using pecl
  Add travis build on PHP 5.5, allow failure
Add note of child README docs to main README
Add (failing) test to make sure default port is added automatically
Fix adding port to IPv6 addresses
Support listening on IPv6 addresses
Add (failing) test to connect to IPv6 address
Support connecting to IPv6 addresses
Fix http-client requirement for socket-client
Merge pull request #184 from reactphp/http-client-require

Fix http-client requirement for socket-client
Allow any `ReadableStreamInterface` on `BufferedSink::createPromise()
Merge pull request #186 from reactphp/sink-factory-readable

Allow any `ReadableStreamInterface` on `BufferedSink::createPromise()
Merge remote-tracking branch 'clue/fix-socket-ipv6'

* clue/fix-socket-ipv6:
  Support listening on IPv6 addresses
Support binding to IPv6 addresses
Merge remote-tracking branch 'clue/fix-socketclient-ipv6'

* clue/fix-socketclient-ipv6:
  Support connecting to IPv6 addresses
  Add (failing) test to connect to IPv6 address
Add IPv6 socket-client to CHANGELOG
Clean up some ipv6 tests
Script to check for missing close events
Rename script