Start new branch with VodPackage class

Making this into a library in addition to a standalone script. The
script will be ported to use the library.
Add header and summary
Raise exceptions when given an invalid configuration
Read the configuration file upon import
Finish most of the media scanning capabilities
Update README
Fixes for VodPackage and initialization
Re-write generator script to use package
Update LICENSE.md
Rename vod_metadata.py to generate_metadata.py
Output in sorted order, fix Run_Time output
Update README.md
Allow module to be executed as a script
Update README.md
Update README.md
Merge branch 'package_clas' of https://github.com/bbayles/vod_metadata into package_clas
Fix bug with category generation
Update default template
Fix bug with reading category configuration
Fix bugs with default values in configuration file