Update loadModelJsonV2 to work with new VertexElement format
Update loadModelJsonV2 to work with new VertexElement format

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branch : feature/json-loader

maxwellalive/engine,playcanvas/engine,shinate/engine,nizihabi/engine,sereepap2029/playcanvas,3DGEOM/engine,sanyaade-teachings/engine,SuperStarPL/engine,MicroWorldwide/PlayCanvas,H1Gdev/engine,sereepap2029/playcanvas,aidinabedi/playcanvas-engine,shinate/engine,playcanvas/engine,3DGEOM/engine,H1Gdev/engine,horryq/engine-1,sereepap2029/playcanvas,MicroWorldwide/PlayCanvas,horryq/engine-1,SuperStarPL/engine,guycalledfrank/engine,RainsSoft/engine,shinate/engine,nizihabi/engine,sanyaade-teachings/engine,horryq/engine-1,RainsSoft/engine,SuperStarPL/engine,maxwellalive/engine,3DGEOM/engine,guycalledfrank/engine,maxwellalive/engine,sanyaade-teachings/engine,RainsSoft/engine,nizihabi/engine,aidinabedi/playcanvas-engine