Using tr command to instead of bourne shell IFS function.

Removed Bourne Shell IFS (http://en.wikipedia.org/wiki/Internal_field_separator) , that not compatible with **zsh** and **dash** .

Tested shell:
```
GNU bash, version 3.2.53(1)-release (x86_64-apple-darwin14)
zsh 5.0.5 (x86_64-apple-darwin14.0)
```

Fixed #431 
 
Signed-off-by: Rack Lin <racklin@gmail.com>