fix numeric pusher bug

- fix that in cell position after partcile push can shifted to [0.0,1.0] due to float rounding errors
- delete old hack for this problem which add 1.0 and substract -1.0 to the position inside of the pusher (thats not solve the problem if the compiler use O3 optimization)
add more comments, change github annotation
Merge pull request #209 from psychocoderHPC/fix-numericParticlePushBug

fix numeric pusher bug