Revert "Tweaked help page contents and fixed a few absolute links"

This partially reverts commit 093ea993098cc63cccb751e8493614dcb0061e76

Restores voting record help section
Change Peer => Senator
Remove part about party whips

I'm not sure this is true for Australia and I don't think it adds much
value to the help message for us so I'm just removing it.
Remove UK specific section about a FOI bill in their parliament
Make Public Whip host configurable in remaining places