Add policy for vetting guest speakers

[kburk1997]

Description of Issue:

Currently, we are very lenient towards allowing guest speakers. There has been controversy in our community on whether or not to allow guest speakers from private companies to give talks on closed-source software.

Proposed Solution:

Document a simple vetting process for guest speakers. A draft policy is asking the following questions:

• What is your talk about?
• How is it related to open source / CS / design / engineering?
• Do you agree to abide by the RCOS Community Code of Conduct in your talk?

[vakrao]

Yeah, I think maybe having external speakers like provide their slides 24-48hrs in advance would be helpful as well to vet them.