1.6.6: support current nightlies and HHVM 4.160

Fixes typechecking with current hhvm nightlies and 4.160.

The release corrects the tag name in the previous release

1.6.6: support current nightlies (expected to support HHVM 4.160+)

Fixes typechecking with current hhvm nightlies (to be released as hhvm 4.160+).

1.6.5: support for limited HTML rendering

See updated README.md.

This release also fixes compatibility with HHVM 4.88.

1.6.4: updated dependencies

This release allows newer versions of some dependencies; older versions are also permitted.

1.6.3: support current nightlies (expected to support HHVM 4.44+)

removes array literals, which are now disallowed by default

1.6.2: support current nightlies (expected to support HHVM 4.38+)

removes assignments as expressions, which are now disallowed by default

1.6.1: support HHVM 4.21+

migrates calls to preg_match[_all]()

1.6: support current nightly builds (4.14-dev)

This release supports 4.13+, including current nightly builds.

Support current nightly builds

This release supports HHVM 4.0, current nightly builds of HHVM, and should also support the upcoming HHVM 4.1 release.

Support HHVM 4.0

This change is identical to previous releases, except for updated version constraints