This option is available in the Settings panel and is not likely to
change often, so we can use the free space there for other means.

(also expand toolbar in compact/standard modes)

This button is almost useless, takes space, can be easily replaced by a
custom button if really needed.

Fix combobox size

Use and install PNG icons instead of ICO, rename P-face to pronterface

 * PNG icons are smaller and there is no advantage in ICO files containing only one resolution
 * It's coomon to name the icon after the app

Update graph.py to 10s/div horizontal scale.

Make temperature graph intervals be 10s as in comments.  Fixes issue https://github.com/kliment/Printrun/issues/491