Added themed paid_preregistrations page

paid_preregistrations.html copied to 8.5 themed folder.
Added Twitter and FB conversion scripts

Added goal conversion scripts to the bottom of the page.
Remove 30 hours reference

Removes the line from badge_choice.html that refers to working for 30
hours to get a badge refund.
Add Legal Name text and explanation

Changes the pre-reg form to say "Legal name" and adds a popup to explain
why.
Merge pull request #370 from magfest/85wordingchanges

MAGFest 8.5 Wording Changes