DMN13 — type conversions are too spread out in Ch 10

The spec does not contain a section where the type conversions are described, hence they end-up spread across the spec. For example, a particular case of invocation conversion is described in 10.3.2.5:

Similarly, on a function f( p ) where the domain of the formal parameter p does not include lists, but on an invocation f( pa ) the
actual parameter pa is a singleton list where the type of pa[1] belongs to the domain of p, then pa[1] should be used instead.

Consolidating all of them in one paragraph will make the spec more readable and easier to change in the future (e.g. we want to apply conversions in other context). It will also help us to identify gaps in the spec.

It's a natural step after adding the type relationships in DMN 1.2.

Add extra paragraph to clarify type conversions

see attached word doc