Clarifies example
Clarifies example

And makes clear the distinction between matching and regex adverbs,
closes #2407

stmuk/doc,perl6/doc,perl6/doc,MasterDuke17/doc,MasterDuke17/doc,MasterDuke17/doc,perl6/doc,stmuk/doc,stmuk/doc,tbrowder/doc,perl6/doc,tbrowder/doc,tbrowder/doc,tbrowder/doc,perl6/doc,stmuk/doc,MasterDuke17/doc,stmuk/doc