The current active branch of Open Conference Systems is ocs-dev-2_3 (https://github.com/pkp/ocs/tree/ocs-dev-2_3). The master branch is currently not under active development.
See https://github.com/pkp/ocs/tree/ocs-dev-2_3/docs for documentation included in releases. General information on Open Conference Systems can be found at http://pkp.sfu.ca/ocs/.