fix character spacing for centered, right aligned, and right-to-left text

The kerning parameters, correctly applied in eTextPara::appendGlyph,
were undone because the characters were repositioned
based on just the glyph width, ignoring kerning.

Instead of recalculating the character positions, just move each
glyph (and its bounding box) with the same offset, keeping
the original spacing.

Signed-off-by: pieterg <pieterg@users.sourceforge.net>