Display tools should not be active until point Cloud is loaded

In case the user starts to play with the display tools (point colors, point scale, point transparency), undefined object error will be raised: 
- geometry is no defined: for point color
- uniforms is not defined: for poitn scale and point transparency

Solution proposed:
- Do nothing, this is no major issue as it will be transparent to the user
- Lock the displaye tab untils points are loaded
