4.0 Release

The ShareFile.Api.Models namespace has moved to ShareFile.Api.Client.Models.
Methods that took a CancellationToken? parameter now take CancellationToken. If you were passing a null value, pass default(CancellationToken) or omit the parameter.
Classes, methods, and properties that were tagged Obsolete have been removed: PlatformFileStream, IPlatformFile, and the ShareFileClient.ZoneAuthentication property.
If you were using PlatformFileStream: all methods/constructors that accepted PlatformFileStream now accept Stream.
If you were using ShareFileClient.ZoneAuthentication: use ShareFileClient.CustomAuthentication.
The ShareFile.Api.Client.Filesystem namespace has been removed.
UploaderBase/DownloaderBase.OnTransferProgress is now an event. If you were assigning a value, use += and -=.
TransferEventArgs and TransferProgress are now structs. Null-checking TransferEventArgs.Progress is no longer necessary.
Upload and download progress is now reported over time intervals. The default interval is 100ms. This value is configurable at FileUploaderConfig/DownloaderConfig.ProgressReportInterval.

Merge pull request sharefile-org#1 from citrix/v3.0.1

Update to 3.0.1