ui: allow changing visual options for graph view

[GTripathee]

For now, changed the line width and font size of the graph view. Can be added more after the discussion.

• also need to talk what is the good ration of small, medium and big.
• and need to translate the string

[Staacks]

Let's discuss presets with the team. About the translations: As these are string resource, they will automatically be added to the translation system if I merge it to the translation branch. There is nothing to worry about except for the English version which will be used as a template by the translators.

But: "Technical" strings like smallValueFontSize or keyLinewidth should not end up in the translation system. Not only would it confuse the translators, but if those strings would actually be different if the user changes language, we would get some interesting bugs. Can we simply use a separate string resource file?

[Staacks]

Edit: Deleted (wrong tab)