Scripts for downloading models in DNN samples
* Initial commit. Utility classes and functions for downloading files
* updated download script
* Support YAML parsing, update download script and configs
* Fix problem with archived files
* fix models.yml
* Move download utilities to more appropriate place
* Fix script description
* Update README
* update utilities for broader range of files
* fix loading with no hashsum provided
* remove unnecessary import
* fix for Python2
* Add usage examples for downloadFile function
* Add more secure cache folder selection
* Remove trailing whitespaces
* Fix indentation
* Update function interface
* Change function for temp dir, change entry name in models.yml
* Update getCacheDirectory function call
* Return python implementation for cache directory selection, use more specific env variable
* Fix whitespace
