Fix new Sherdog UI + fix wrong opponent/ref/event + change get_text() to .text + fix encoding to UTF8

[DanMcInerney]

New sherdog UI requires these changes thanks to previous PR from mmedek.

Also, the current branch mixes up the opponent/ref/event very significantly. I have fixed this, but my fix means the referee is often not found if the ref doesn't have an href link. But that's inconsequential for most use cases. The accuracy of the opponent was the major pain point as "opponent" was very often the event name or the ref's name and that has been fixed with a more accurate search of the HTML.

The last fix was to ensure the output would be UTF8 encoded rather than Windows ISO encoded. This makes the resulting data much easier to deal with.

For future:

• add a function which only updates based on recent events, rather than grabbing the entirety of the fighter DB as grabbing entire DB takes 6+ hours on a decent connection.
• Add async functionality to dramatically speed up the gathering of fights and events