make object's 'Content' type more generic (from *bytes.Reader to io.Reader)
Merge pull request #183 from jrperritt/cf-change-reader-to-interface

make object's 'Content' type more generic (from *bytes.Reader to io.Read...
Merge pull request #184 from jrperritt/v0.2.0

move 'NewClient' to function
remove unused files from previous version; they are confusing people.