Performance testing

23/04/2008
	249 143 msec for 10 iterations on tests/text/ditaa_bug.txt
28/04/2008
	186 817 msec for 10 iterations on tests/text/ditaa_bug.txt (25% faster)
24/03/2009
	124 531 msec for 10 iterations on tests/text/ditaa_bug.txt: Due to java 6 (50% faster)
25/03/2009
         41 721 msec for 10 iterations on tests/text/ditaa_bug.txt: Due to StringBuffers in TextGrid (83% faster)
