Update requirements to depend on requests>=1.1.0

The latest version of requests is 1.2.3 and pinning requests-kerberos's
required version to exactly 1.1.0 means it can't be used by an app that
already has a pinned requirement on requests 1.2.3

Refs #14
Minor fixes in the README
Merge pull request #19 from dpursehouse/doc-updates

Minor fixes in the README
Merge pull request #18 from dpursehouse/update-requirements

Update requirements to depend on requests>=1.1.0
Add myself to the authors list
Update history for version 0.4
Merge pull request #22 from dpursehouse/add-myself-to-authors-and-update-history

Add myself to authors and update history