overlay: options tab(s) clean up (#598)

## Description of change
Merge option name and command line parameter columns.
Expand the size of widget column.
In Search tab, add a new column to display the category.
Add a highlight effect to rows when hovered over - apply this to all
tables in the configurator UI.

src/spice2x/overlay/imgui/extensions.h

@@ -20,4 +20,5 @@ namespace ImGui {
     void TextTruncated(const std::string& p_text, float p_truncated_width);
     bool DeleteButton(const std::string& tooltip);
     bool ClearButton(const std::string& tooltip);
+    void InvisibleTableRowSelectable();
 }