The routine gSetStrJustify() sets the current string justification.
Left justification (the default) is where the string is drawn starting from the current position from left to right and the current position is left at the lower right end of the character string.
Centre justified strings are positioned such that the string is centred at the current position. The current position after a centre justified string is left at the bottom centre of the string.
For right justified strings, the string is positioned such that the end is at the current position. The current position after a right justified string is at the bottom left of the character string.
Justification affects all string and numeric output except gDrawMarker() and the effect of gMoveToNextLine().
