HTTPS on docs.nwjs.io

[martinsuchan]

Although the homepage nwjs.io is on HTTPS only, the docs page isn't. This should really be fixed. Free Let's Certificate is a good option here.

Just a note, the HTTPS configuration on nwjs.io is also not perfect.

[ghostoy]

@rogerwang That requires some configurations on our own server. See http://docs.readthedocs.io/en/latest/alternate_domains.html#cname-ssl