Support ConditionExpression for DeleteItem

[d2a4u]

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It is possible to pass a ConditionExpression to DeleteItem request so that the deletion is only perform under certain condition. https://docs.aws.amazon.com/amazondynamodb/latest/APIReference/API_DeleteItem.html#API_DeleteItem_RequestSyntax

[missingfaktor]

Hey, Duc! I can pick this up if you'd like me to. :-)

[d2a4u]

hey, that would be great! Thanks. There is already an Expression model which is being used for put which might be a good starting point.

[missingfaktor]

PR: https://github.com/d2a4u/meteor/pull/181