TBD notes

[abeyer]

This is a tracking issue for "TBD" items in the copy that need to be updated

• dining_guide.rst:177
• talk_slides.rst:22
• talk_slides.rst:41
• index.rst:83
• index.rst:85
• index.rst:87
• travel_guide.rst:55

[ndenny]

Update:
talk_slides: TBDs are the Lightning Talks (determined on the day)
index: Location of pre-conf social. Fixing this now.

[ndenny]

Spotted one other ?? in index.rst: "Check out the job board in ??."