0013557: field values display
Updated in accordance with changes in fonts in GUI_SRC
QtxFontEdit class and related controls in preferences has been updated in order to support custom fonts instead of system fonts only. For example VTK viewer uses only three fonts Arial, Courier and Times. As result there is no point in providing control with system fonts for VTK viewer. Also ?S? button has been added in QtxFontEdit in order to provide ?Shadow? style of VTK font. ?1underline? property of QFont is replaced with ?overline? property in order to store ?Shadow? status of font to avoid conflict simultaneous usage of ?U? and ?S? button.
