Migrated the project to netstandard1.3

Migrated the project to netstandard1.3 in order to enable cross platform usage.

No content no parsing

Major

• Refactored the client so that it no longer throws an exception if the received response has no content. Only if there is content, will the client attempt to parse it.
• BREAKING Refactored the client so that it returns HalHttpResponseMessage instances, rather than parsed RootResourceObject instances directly. The new message object allows the consuming code to access the Location header as well as status information.

Minor

• Updated nuget packages
• Extended and updated documentation

Version 1.3.0

Changes:

• Removed the NonParsingHttpClient abstraction. The underlying HttpClient is now simply exposed as a property of the IHalClient instance.
• Stopped using AssemblyVersion for versioning the nugget package. Instead i am now using AssemblyInformationalVersion in order to version the package in a more controlled manner.
• Bumped minor version as there has been a breaking change.