Wrappers for value and input

[fatadel]

node-wot approach:

The body of a request is already considered as a new value when writing to a property. It is also possible to wrap it around {"value": ...value...} and node-wot will unwrap that. But the first way is preferred.

The body of a request is already considered as an input when invoking an action. It is not possible to wrap it around {"input": ...input...}.

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wot-py approach:

It is mandatory to wrap property values with {"value": ...value...} and action inputs with {"input": ...input...}.

[fatadel]

Some additional notes.
When using the wot-py servient as a client it wraps/unwraps everything behind the scenes, so that consumed_thing.writeProperty(propertyName, value) is enough. However, this is a problem when using a custom client or a client from node-wot.
This also makes it impossible to use a wot-py client for node-wot servients, because wot-py always assumes the value is wrapped inside {"value": ...value...} but it is not wrapped in node-wot.