[SIXSTEPS-4152] Add janus version 0.2.2 checkout

Fix copying of the config files

Update readme

Add admin port to the expose command

Enable access to the admin endpoint over http transport

[SIXSTEPS-4152] Remove janus version checkout (use latest janus version on master)

[SIXSTEPS-4152] Add janus docs configuration

[SIXSTEPS-4152] Readme: Fix build command

Update janus gateway to 0.2.2

Replace libsrtp 1.5.0 with 2.0.0

Merge pull request #1 from sjkummer/master

Use libsrtp2 to reduce risk of broken interoperability with future WebRTC versions

Update janus gateway to v0.2.1

Revert "[SIXSTEPS-3962] Remove janus v0.2.0 checkout command"

Update stun server information