Update main.js dashboard.css responsive webpage work

Switching dashboard between 3 and 4 columns, by moving motor gang boxes. 

Looks good in 4-column arrangement on a computer screen, for example. Then make the screen skinnier, it'll flip to be 3-columns, width gangs under the motors.

Looks good in 3-column arrangement, vertically on an iPad screen.

Text editor html element (#textEditor) and control panel html element (#gameWorld) widths are set from main.js, based on changing game canvas sizes. Text editor buttons move as well. This done all through an adjustHtml function in main.js.

Some issues- zooming & scroll on touch screen device. Issue with page zooming and then being unable to zoom out, without being to reach scroll bars on right and bottom edges.

Need to work on smart phones better next.