Add comments to utils, remove unused functions and add isModel
Add comments to utils, remove unused functions and add isModel

Rathunter/vizabi,TBAPI-0KA/vizabi,alliance-timur/vizabi,IncoCode/vizabi,maximhristenko/vizabi,logicerpsolution/vizabi,maximhristenko/vizabi,dab2000/vizabi,jdk137/vizabi,alliance-timur/vizabi,Gapminder/vizabi,acestudiooleg/vizabi,homosepian/vizabi,IncoCode/vizabi,sergey-filipenko/vizabi,maximhristenko/vizabi,Rathunter/vizabi,buchslava/vizabi,IncoCode/vizabi,logicerpsolution/vizabi,vizabi/vizabi,Rathunter/vizabi,dab2000/vizabi,buchslava/vizabi,Gapminder/vizabi,jdk137/vizabi,TBAPI-0KA/vizabi,dab2000/vizabi,alliance-timur/vizabi,homosepian/vizabi,TBAPI-0KA/vizabi,sergey-filipenko/vizabi,acestudiooleg/vizabi,acestudiooleg/vizabi,jdk137/vizabi,Gapminder/vizabi,homosepian/vizabi,vizabi/vizabi,sergey-filipenko/vizabi,buchslava/vizabi,logicerpsolution/vizabi