Add freeleech-percents filter option. Closes #2

A comma delimited list of freeleech percentages to match.
Example: freeleech-percents: 25,50,75
Add freeleech-percents support to Awesome-HD
Add tags to Awesome-HD

This allows matching based on release tags not assigned to their own
filters.
These include, but are not limited to, DXVA, AHD Gold, TrueHD, DTS.