[Telepathy] Proposed spec format update: Dict<A,B>

[Alp Toker]

We do not currently mark up dictionary parameter types:

Before:
       <arg direction="in" name="aliases" type="a{us}"/>

I propose:

       <arg direction="in" name="aliases" type="a{us}" 
tp:type="Dict<Contact_Handle,String"/>

This is inspired by the format we already use to describe arrays and 
based on the syntax for templates in C++ and generics in C#. It is 
surprisingly easy to parse recursively in XSL.

For primitive (D-Bus) types, we will use the Telepathy_Camel_Case form 
of the names specified in the D-Bus spec:

Byte, Boolean, Int16, UInt16, Int32, UInt32, Int64, UInt64, Float, 
Double, String, Object_Path, Signature, Variant