annotate skippable edge elements

For example, ## hasAgentCollection.edge.choice |= hasAgentCollection.edge.def hasAgentCollection.edge.def = a collection of Agents. element hasAgents { hasAgentCollection.type.def } ==> The information about what edge elements are skippable can be propagated into the schema documentation by adding to the description in the RNC modules. ## hasAgentCollection.edge.choice |= hasAgentCollection.edge.def hasAgentCollection.edge.def = ## a collection of Agents. Skippable. element hasAgents { hasAgentCollection.type.def } These definitions are contained in the modules in LRML stripe_optional_module.rnc stripe_optional_ruleml_module.rnc In the RuleML modules, these definitions are not kept together in one module, but are distributed across many.