various plotting bugs

investigations of the new plotter test cases have revealed various bugs, namely

• gap between ratio and main plot
• x label offset inconsistent between showSub true/false
• showTitle=false doesn't work
• showDoverBminusD plot looks broken and needs to be redone
• normalize / normalizeToTotalBkg - don't look like they do what they should
• TQPlotter.cxx createPad bug: there's a dot missing
• Documentation of geometry.*.textSize wrong