Rename Repo to Repository and minor changes / Import samples project

[azabbasi]

In this PR :

• Rename ModelsRepoClient to ModelsRepositoryClient (along with all related file and class names like options and test base classes that borrowed the name of the client)
• Remove getter and auto property for ClientOptions as per Krzysztof's comment
• Bring over Samples project and clean out the parser related pieces
• Rework Exception handling in RemoteModelFetcher to include status code and other exception fields from the originally thrown exception.

One outstanding question is regarding the LocalModelFetcher exception handling. When LocalModelFetcher throws a RequestFailedException there is no outgoing HTTP call and as a result there is no status code attached to the RequestFailedException which in my opinion is the correct behavior as there is no HTTP stack involved. on the other hand, the consumer might be relying on the status code. we have to have a brief discussion about that.

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