Make extended vs. simple distinctions clearer

[olorin]

queueExtended will set the LSB of an address before write, but there's no equivalent functionality for queueing sourcedict updates, so the user still needs to keep track of the LSB theirself. This seems error-prone.

Two options come to mind:

• Add queueSimpleSourceDictUpdate and queueExtendedSourceDictUpdate, and ?deprecate queueSourceDictUpdate.
• Add hashSimpleIdentifier, hashExtendedIdentifier, requestUniqueSimple and requestUniqueExtended, and deprecate hashIdentifier and requestUnique.

Setting the LSB appropriately on generation seems to be better than setting it in all the places an address is used; however, this soft-breaks the (presumed desirable) support for users generating their own addresses.

Thoughts? @oswynb @tranma @christian-marie @afcowie

[christian-marie]

GADT might provide a cleaner API.