addUtteranceToCollection = function (attribute, srcItem, matchInTarget) {
    if(attribute === 'text') {
        matchInTarget.utterances.push(srcItem); 
    } else {
        matchInTarget.utterances.push(new helperClasses.uttereances(srcItem.pattern.replace('{', '{@'),srcItem.intent,[]));
    }
}
helper function to add utterances to collection based on src type (pattern or utterance)
@param {string} attribute attribute to check on and copy over
@param {object} srcItem source object
@param {object []} matchInTarget target collection of objects
@returns {void}