Fixing typo in PolylineChildModel factory name

Changing "ugGmapPolylineChildModel" to "PolylineChildModel".ns()
Fixing typo in PolylineChildModel factory name

ugGmapPolylineChildModel -> uiGmapPolylineChildModel
Merge pull request #881 from bensgroi/master

Fixing typo in PolylineChildModel factory name