add support for unmarshalling gNMI TypedValue

[g-yusufsn]

Change includes;

• Adding unmarshalling support for gNMI TypedValue
• Modifying retriveNode to use unmarshalGeneric function to unmarshal gNMI TypedValues
• Fixing a bug where we should return an error in SetNode if path points to a non-leaf schema

[coveralls]

Coverage decreased (-0.06%) to 91.107% when pulling 50247c7 on unmarshal-gnmi into d19e6ae on master.

[g-yusufsn]

I guess we are broken due to grpc/grpc-go#2428. We need to remove it from the list of go versions we are building against.

[robshakir]

Yep - I'll make this change. We should deprecate 1.8 at this point. It seems fair enough to only handle head - 2. Will make this change and review your PR when I am at a computer in a couple of hours. Thanks! r.

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On Fri, Nov 2, 2018, 5:57 PM g-yusufsn ***@***.***> wrote: I guess we are broken due to grpc/grpc-go#2428 <grpc/grpc-go#2428>. We need to remove it from the list of go versions we are building against. — You are receiving this because your review was requested. Reply to this email directly, view it on GitHub <#252 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AEnN1VbiwkU_TdwXFCLU6LJXjxDeEr6eks5urOoMgaJpZM4YMDSE> .

[g-yusufsn]

I just created PR and sent to you. Feel free to review whenever you have time. Thanks for the reply!

#254

[robshakir]

LGTM, thanks for the change!

[g-yusufsn]

Thanks for the review!