various optimizations to make CYK+ parser several times faster and eat less memory.

speed-up of decoding depends on how much time is spent in parser:
10-50% speed-up for string-to-tree systems observed (more on long sentences and with high max-chart-span).

if you only use hiero or string-to-tree models (but none with source syntax), use compile-option --unlabelled-source for (small) efficiency gains.