[Pattern-matching] navigation shorcut

[CafeKrem]

RBVariableNode suchAs: {
    #name -> #'@name'.
    #methodNode -> RBMethodNode suchAs: {
        #methodClass -> Class suchAs: { 
            #slotNames -> #( #'*' #'@name' #'*')
        } 
    }
}

become

RBVariableNode suchAs: {
    #name -> #'@name'.
    #'methodNode methodClass' -> Class suchAs: { 
            #slotNames -> ContainMatcher element: #'@name'
        }
}

or become this

RBVariableNode suchAs: {
    #name -> #'@name'.
    #'methodNode>methodClass' -> Class suchAs: { 
            #slotNames -> ContainMatcher element: #'@name'
        }
}

[CafeKrem]

fix with PR #32