[BUG] - documentation should include a general reference to all notation

[mprather]

Description

The OML spec uses some notation that is not clearly identified up front or at all.

For example,

• the :> symbol is not described the first time it is used.
• * and ? are never described.
• [] in the context of [A | B]
• ()

Expected Behavior

All of the notations should be clearly identified up front before they are used.