acu185196 - added v4 signature and made it the default
added v4 signature to S3 (+ S3 links)
S3 Put fix
Be a bit more clever when parsing S3 endpoints
Fix host parsing for services other than S3
Some V4 specs
More V4 signature tests
Version bump to 0.2.1
Merge pull request #11 from rightscale/cfDJR_14_22_acu185196_add_v4_signature_support_v2

Cf djr 14 22 acu185196 add v4 signature support v2