[minor] Update Engine.IO and SockJS client libraries to their latest versions
[major] HTTP Access Control (CORS)
Add primus-cluster plugin in README.
Merge pull request #171 from neoziro/add-primus-cluster-to-readme

Add primus-cluster plugin in README.
[fix] Fix an issue with the hash of reserved events in IE8

see https://github.com/cayasso/primus-emitter/issues/21
Revert "[major] HTTP Access Control (CORS)"

This reverts commit aaf108c60fd1fe98b3b1fe9c20b2166cbc565b80. As the master branch
has a change that needs to be released first. CORS is still implemented in a our
`cors` branch and will be released as 2.1
[dist] 0.0.4
[fix] Update the Engine.IO client build tool to reflect the changes added in the offical build
[minor] Rebuild the Engine.IO client