Initial commit for the addition of TIMIT dataset
@patrickvonplaten could you please review and help me close this PR? @lhoestq  Thank you so much for your comments and for patiently reviewing the code. Have _hopefully_ included all the suggested changes. Let me know if any more changes are required.

Sorry the code had lots of silly errors from my side!:' Will be more careful from next time! :)



Below points needs to be addressed:

- Creation of dummy dataset is failing
- Need to check on the data representation
- License is not creative commons. Copyright: Portions © 1993 Trustees of the University of Pennsylvania

Also the links (_except the download_) point to the ami corpus! ;-)

@patrickvonplaten  Requesting your comments, will be happy to address them!