Reduce ord() calls in total by ~74% on plain start

Reduces the total amount of ord() calles from 152602 to 39075 (26% left) on
normal OntoWiki start (news page, no model loaded), which reduces the
total impact of Turtle Parser's _isWS() by ~20% (from 32% to 10%)

Decreases load time on my system by 23%
Merge pull request #62 from AKSW/feature/spacerocketingSpeedup

Reduce ord() calls in total by ~74% on plain start