Add TestAttachmentFromByteArray
Mark unused props on AccessToken and RequestToken as [Obsolete,true]
Update source/XeroApi/Model/Organisation.cs

Added time zone property.
Merge pull request #26 from TDaphneB/master

Time zone available on organisation.
Merge branch 'master' of https://github.com/XeroAPI/XeroAPI.Net
Increment version to v1.1.0.28
Merge https://github.com/XeroAPI/XeroAPI.Net
Update Build number to .28