Fixed filtered scope host not used in request headers

Conflicts:
	lib/intercept.js
Fixed issues with mismatching case header names
Fixed an issue with request header not set to filtered scoped host
Fixed request header matching for special case of host
Added suppress_reqheaders_recording recording option
Renamed headerKeysToLowerCase to headersFieldNamesToLowerCase for clarity
Set the storage of headers field names to lower-case throught Nock
Changed semantics of recording options with enable_reqheaders_recording
Header field user-agent is now deleted case-insensitively
Convert target for matcher to string before calling match (fixes #197)
Allow matching header with a function
Merge branch 'fix-request-header-matching'
v0.35.0
Merge branch 'issue-197' of github.com:lakenen/nock into lakenen-issue-197
Merge branch 'lakenen-issue-197'
Merge branch 'header-match-fn' of github.com:lakenen/nock into lakenen-header-match-fn

Conflicts:
	tests/test_intercept.js
Merge branch 'lakenen-header-match-fn'
v0.36.0
response.client.authorized for SSL. fixes #158
v0.36.1
clarifying that scope.filteringPath should only be used once per scope. fixes #145