Add rebuild on glsl shader code change in grunt watch command
Add rebuild on glsl shader code change in grunt watch command

kkuunnddaannkk/osgjs,jtorresfabra/osgjs,cedricpinson/osgjs,hishamabdelrahman/osgjs,cedricpinson/osgjs,jmirabel/osgjs,cedricpinson/osgjs,kkuunnddaannkk/osgjs,kkuunnddaannkk/osgjs,jmirabel/osgjs,hishamabdelrahman/osgjs,gideonmay/osgjs,gideonmay/osgjs,hishamabdelrahman/osgjs,jtorresfabra/osgjs,jmirabel/osgjs,gideonmay/osgjs,jtorresfabra/osgjs