Add Windows script for generating SSL certs needed for SAML2 login flow

[humphd]

In #448 and #449 we're working on getting the SAML2 login flow working, and it will require SSL certs for development and testing. We have a script to do it on *nix, but not Windows.

There are a number of ways this can be done, see https://medium.com/the-new-control-plane/generating-self-signed-certificates-on-windows-7812a600c2d8. This fix needs to do at least 2 things:

• add a script to tools/ that can be run in a Windows shell and will generate these certs
• add a line to the Windows install portion of the .travis.yml file to run the script in CI

[manekenpix]

@Grommers00 I found Microsoft documentation with multiples examples of how to create a certificate depending on your needs. I created a certificate using the first example, but since I'm not really sure what the certificate is for I couldn't test it with telescope. Let me know if it helps or if there's anything I could do to test it.

[Grommers00]

Awesome! Thanks I'll take a look!