Include Windows python command on README.md

[tshefi]

The readme.md file includes command examples, all of which are Linux based, however some of the students use Windows based laptops. The commands are similar but not identical, IMHO adding the Windows command version, where possible, may reduce: frustration, confusion and help speed things up, especially on the hackathon days, where time is of the essence.

Example
(Linux) ./rose-server <---> (Windows) python rose-server
(Linux) source ~/.venv/rose/bin/activate <---> (Windows) .venv\rose\scripts\activate