Protocol Generator extension

[5A11]

• pt:union within pt:optional is currently not working.
• Custom types within pt:lists and pt:sets are not supported.
• The key in a pt:dict cannot be ct:xxx, pt:float, or pt:bytes.
• There is currently rounding errors involving pt:float.
• Custom type names' reg ex may need updating to reflect CamelCase.
• update documentation to reflect the latest state.