use httptest.Sever for testing
replaced tests against httpbin.org with httptest server

unearthed an error in Id("delete",r), where another / is appended to the base url
just use a single test server
Merge branch 'httptestServer' of https://github.com/cryptix/gopencils into cryptix-httptestServer

Conflicts:
	resource_test.go
Merge branch 'cryptix-httptestServer'