Merge pull request #71 from danswain/master

Initial work on adding PayPal ExpressCheckout endpoint to Sevendigital.Api.Wrapper.
automated package build and version number increment to 5
Revert "automated package build and version number increment to 5"

This reverts commit 382b77b04f49527341e4b04e42bd76e666bc1b4a.
automated package build and version number increment to 5
Merge pull request #72 from danswain/master

Nuget Package Update
completing paypal purchase needs post attribute
Merge branch 'master' of https://github.com/7digital/SevenDigital.Api.Wrapper