changelog update

version bump

new version: misc. fixes.

Merge pull request arskom#90 from plq/master

2.4.0 commits. see changelog.

new version: ByteArray, rate limiting, better documentation.

new version: sqlalchemy.orm.relationship support, better events, bett…

…er docs

new version: a better HttpRpc protocol.

Merge pull request arskom#85 from plq/master

XmlObject as out_protocol is working.

fix documentation bugs

new version: fixed setup script