Add filter for dropping cookie from propagated request (e.g. dropRequestCookie)

[oporkka]

Is your feature request related to a problem? Please describe.

We want to be in control of cookies in our Skipper level, and prevent certain cookies to be propagated to backends.

Describe the solution you would like

A cookie like dropRequestCookie would help us here. It would go through the cookies in the Cookie header, and drop the cookie with the matching name. It would be kind of opposite to requestCookie, which adds a cookie with a certain name and value to the request

Describe alternatives you've considered (optional)

Use requestCookie to set the desired cookie value to an empty string, when propagating the request to the backend. It will avoid big cookie data values to be propagated, although the cookie name will be still propagated.

Would you like to work on it?
Yes, possibly, but little time