SPTK 3.7

The Speech Signal Processing Toolkit (SPTK) is a suite of speech signal processing tools for UNIX environments.
e.g., LPC analysis, PARCOR analysis, LSP analysis, PARCOR synthesis filter, and other extended versions of them.
This software is released under the Modified BSD license.

It's my first time to send pull request, if any problems, let me know.
I'm happy to know and correct it.