Added encoding script downloadsounds.py and simple_usage.m (this script demonstatres how to use, if you are inpatient)

This script add generator only, the MATLAB api will be in next commit.
If you are unlukcy to generate, you can download generated samples from https://mega.co.nz/#!cFtWRRST!a8NfNm_O4XlKXo8eS6FsV0z9nGJsn730CD89zhOeVIQ (938.6 MB) this file doesn't contain file size struture update