Improves speed of the functions

Two improvements:

1. Compiles most of the PS functions (FunctionType 4) into JavaScript (based on samples extracted from test pdfs, see https://gist.github.com/yurydelendik/7f0e47927886112b7a96)
2. Don't create arrays as output -- result is placed into existing array.

http://www.coachusa.com/CoachUsaAssets/files/97/route45.pdf was used for testing, improvements:

1. 3700ms => 800ms
2. 3700ms => 3300ms