Run script fails on HTTPS endpoints

[JamesLaverack]

When load testing a sock shop secured by HTTPS, there is no way to give the https:// address as the script places the prefix http:// on the host.

As a workaround, a user can execute locust directly, for example:

locust --host=https://sock-shop.example.com -f locustfile.py --clients 10 --hatch-rate=5 --run-time=1m --no-web --only-summary