NancyFx/Nancy — pull request #639 by thecodejunkie (2012-06-12 06:30:57+00:00)
Title: Made RequestHeaders writeable

You can now change the value of the request headers. If you assign a header
the default value of the return type (for instance null for a string) then
the header will be removed from the keys collection until a new value is
assigned

Fixes #281