Matched parameters' values are always strings

[mgv99]

When getting the value of a matched parameter in a state body, e.g. temperature = predicted_intent.get_parameter('temperature').value we always obtain a str object, therefore, we cannot do if temperature > 0, since it is a string object. We can simply cast the object to its proper type, but it adds complexity to the body of the state. We could implement a flexible type value, at least for the following basic types:

• [ ] str
• [ ] int
• [ ] float
• [ ] datetime
• [ ] bool (can a user actually write a bool value in a message?)