Added pages for upcoming UK boot camps
New page for American University of Beirut camp
Changed coordinates as per @wking's comment.
Merge pull request #312 from gvwilson/master

Updating material for the instructors' guide.
Merge pull request #311 from amyrbrown/beirut-post

New page for American University of Beirut camp
Two more boot camps (Alberta and Massachusetts) in May
Merge pull request #308 from mikej888/master

Added pages for upcoming UK boot camps
Removed pages for boot camps which do not have definite dates
Merge pull request #314 from mikej888/master

Withdrew vague boot camp pages
Added the room number to the UC Davis bootcamp page
Merge pull request #315 from amyrbrown/ucd-room-num

Added the room number to the UC Davis bootcamp page
Boot camp at UWM
Command to display history graphically in Git
Taking out UMass until details settled, adding Tufts
bootcamps: Add 'restricted' metadata to restricted bootcamps

I may have missed some, since I only tagged bootcamps found with:

  $ grep -i restrict bootcamps/*.html
compile.py: Parse the new 'restricted' metadata

The value is just a string, so use 'true' or '' for True/False, taking
advantage of the fact that bool('') == False.
bootcamps/index.html: Different markers for restricted boot camps

I made the marker legend a paragraph, since I was concerned about a
wide table if we went with:

  ? Future Open Boot Camps  ? Future Restricted Boot Camps  ...

and a grid of future/past open/restricted seemed too confusing ;).
The paragraph should flow reasonably well, even on narrow screens.

I also removed the in-tree versions of the old pins, since I haven't
checked the legality of that [1], and if we can't get to
chart.apis.google.com to fetch the markers, we're probably not going
to get the map from maps.googleapis.com either ;).

If the number of markers continues to grow, it may be worth bundling
them into some sort of structure to avoid duplicate entries in the
JavaScript header and the in-body legend, but I don't think we're
quite there yet.

[1]: https://github.com/swcarpentry/website/pull/192#issuecomment-11928689
bootcamps/index.html: Label restricted bootcamps in lists

I just append '(restricted)' to the venue, but we could add a new
table column.  We could also add a 'restricted' class if folks want to
do some CSS styling.  Hopefully these restricted boot camps are rare
enough that such special handling isn't worth the effort ;).
Removed registration form (temporary, until registration opens).
Merge pull request #317 from amyrbrown/ua-registration

Removed registration form on Arizona camp page (temporary, until registration opens).