Integrate serialization customization on property-by-property basis

[VigneshVSV]

Currently, JSONSerializer is the default serializer for all operations. One can change the serializer altogether to pickle or MessagePack, but not property by property basis.

However, for numpy arrays or very select custom data types like dataframes, it would be beneficial if only that property serialized in a different way compared to other properties like Number, String, simple lists etc. which may still be serialized with JSON.

Possible steps involved

• Verify how param deals with it? They also have built in JSON serializer & JSON schema generation which needs to be integrated anyway. A serialize() and deserialize() method is already available parameter-by-parameter/property-by-property basis in param
• If serialize() and deserialize() is good, add corresponding logic and add an argument to property init which accepts the serializer type or the serializer itself
• Change EventLoop property execution to factor serialize and deserialize methods
• Add corresponding content type headers for HTTP
• In ZMQ Object Proxy, factor the serializer

As an extra effort, as the first point states, if param's built in serialization is taken into account, that would be great!