update FAQ with some basic how-to-use flatpak app

[tssc7my0no7]

this pr adds some basic information on using the flatpak application

[biodranik]

Suggested change

	To install OM on linux with flatpak, open the terminal and imput `flatpak install flathub app.organicmaps.desktop`
	To install OM on Linux with flatpak, open the terminal and input `flatpak install flathub app.organicmaps.desktop`

[biodranik]

Suggested change

	Once the app is installed you cam use the scroll wheel of your mouse or the controlls on the right menue bar to zoom into the area you wish to navigate in order to download maps for that area. You can also click the "download" icon in the lower right. Once you have downloaded maps for the regions you care about, the app should work even without an internet connection.
	Once the app is installed you can use the scroll wheel of your mouse or the controls on the right menu bar to zoom into the area you wish to navigate in order to download maps for that area. You can also click the "download" icon in the lower right. Once you have downloaded maps for the regions you care about, the app should work even without an internet connection.

[biodranik]

Suggested change

To perform routing and turn by turn navigation, you have a couple of options. if you know the gps cordinates of your starting point and ending point, you can click the settings icon (above the green checkmark) and input the cordinetes of your starting point and destination. To set the starting point on the map itself, click the navigation icon and select "start point", then hold down the shift key and left click on the map. To set the destination, change to "end point" and click a location on the map.

To perform routing and turn by turn navigation, you have a couple of options. if you know the GPS coordinates of your starting and ending points, you can click the settings icon (above the green checkmark) and input the coordinates of your starting point and destination. To set the starting point on the map, click the navigation icon and select "start point", then hold down the shift key and left-click on the map. To set the destination, change to "end point" and click a location on the map.

[biodranik]

Suggested change

	To add a location to your bookmarks, hold down the Alt key and right click the place you want to bookmark. The bookmark may not be immediatly visible, to view and manage bookmarks you need to click the red star icon.
	To bookmark a location, hold down the Alt key and right-click the place you want to bookmark. The bookmark may not be immediately visible, to view and manage bookmarks you need to click the red star icon.

[biodranik]

What does it mean "may not be immediately visible"? It looks like a bug. Does it always reproduce?

[biodranik]

Suggested change

	Currently the Linux desktop app is mostly used for development purposes (automated testing and checking logic without having to compile for mobile) but it would be great if developers were able/willing to help improve its useability.
	The Linux desktop app is mostly used for development purposes (automated testing and checking logic without having to compile for mobile). Any volunteers to improve the usability of the Linux version are welcomed!