Req 4.1 unclear

[pebau]

Req 4.1 says: "If an encoding HTTP header (Accept and Accept-Encoding) is provided then a representation of the coverage in the format indicated SHALL be returned."

I believe what is intended is: "If an encoding HTTP header (Accept and Accept-Encoding) is provided in the request then a representation of the coverage in one of the formats indicated SHALL be returned."

[Schpidi]

Teleconference 20190503: This requirement may not need to be here at all. Content negotiation is likely inherited from common and HTTP 1.1.

[Schpidi]

This requirement isn't present anymore as it is inherited from OGC API - Common. The language in the README.md has been adjusted.