Icons links:
* expand.png -- https://icons8.com/icon/1755/Expand
* collapse.png -- https://icons8.com/icon/1757/collapse
* update.png -- https://icons8.com/icon/25224/available-updates
* undo.png -- https://icons8.com/icon/3059/Undo
* redo.png -- https://icons8.com/icon/3060/redo
* openSimplemap.png -- https://icons8.com/icon/2828/Open
* save.png -- https://icons8.com/icon/18765/save
* showObservations.png -- https://icons8.com/icon/25169/CBS
* showObservationsTree.png -- https://icons8.com/icon/11241/tree-structure
* showConfig.png -- https://icons8.com/icon/364/settings
* showConfigInWindow.png -- https://icons8.com/icon/364/settings

