v2.1.0 Release notes

In this release, Miniworld has been updated to support Gymnasium 0.29.1 and 1.0.0+, along with minor changes to the website.

In addition, a ManualControl class has been added for easy testing by users in miniworld.manual_control (#94). The *.mtl loading was more robust, and position specification is now feasible for place_agent. Add a StochasticAction wrapper for users who wish to take random actions for a percentage of the time.