Add support to IntentBuilder() for no names

[penrods]

This allows creation of intents with no name. The names are not used internally within Adapt, but this is particularly useful within other ecosystems such as Mycroft Skills which can automatically name the intent appropriately from context.

[penrods]

Ping!

[MatthewScholefield]

Closing this in favor of using a subclass for other ecosystems that set it on their own terms.