Say hello to the first settings page in our shiny new, almost working SettingsDlg...

Now you can set the ChatWidget's fonts. To make this work, I made UiStyle (and
automagically its derived classes) remember custom set formats. Also, default formats
can be restored. This allows to change, save and restore all the style's formats
at run-time...
For now, in the settings dialog you can only edit the ChatWidget's base fonts, but later on
we will certainly allow more tweaking of the current style.