Upgrades to summit video pages

Conflicts:

	openstack/code/Presentation.php
	openstack/code/PresentationCategoryPage.php
	openstack/code/summit/SchedToolsPage.php
	themes/openstack/templates/Layout/PresentationCategoryPage.ss
	themes/openstack/templates/Layout/PresentationCategoryPage_presentation.ss
Fixed a condition that could cause an object not found error.
Not all videos seem to get the maxresdefault from youtube. :( Switching back to a different thumbnail.
[smarcet] - #7691
* fix for borken dates on presentations.

Conflicts:

	openstack/code/Presentation.php
Fixes for page display and featured videos

Conflicts:

	openstack/code/PresentationCategoryPage.php
More video page fixes

Conflicts:

	openstack/code/PresentationCategoryPage.php
Added keynote videos as a top section and labelled the top video as the most recently added.
Updated homepage verbiage
One more home update with verbiage feat. Todd M.
[smarcet] - #7742
* fixed slug method on datacenter locations on js side.
[smarcet]
* ss3 migration fixes.

Conflicts:

	marketplace/code/model/consultants/ISpokenLanguage.php
[smarcet]
* migration fixes for ss3.
[smarcet] - #7612
* refactoring

Conflicts:

	openstack/_config.php
	themes/openstack/templates/Layout/SangriaPage_SetCategorySponsors.ss
	themes/openstack/templates/Layout/SangriaPage_ViewSponsorsRequest.ss

Conflicts:

	openstack/_config.php
	openstack/code/SangriaPage.php
	themes/openstack/templates/Layout/SangriaPage_AddInvolvementType.ss

Conflicts:

	openstack/code/SangriaPage.php
Minor improvements to the election system. Mostly, replacing hardcoded dates with dynamic ones and adding a field to specify the date that a candidate application must be accepted.

Conflicts:

	registration/code/EditProfilePage.php
Quick fix to change date formatting in nomination email.
Changed text of email slightly from day of week to day of month.
Updated "See the Current Nominations" link on Election page.
Minor change to candidate list link
Fixed security backlink to lead directly to this page (/profile/election/ rather than /profile/)

Conflicts:

	registration/templates/Layout/EditProfilePage_election.ss
Added condition to check for being a non-foundaiton member. You are now told that "Your account credentials do not allow you to nominate candidates." and asked to try another account (if you have one) or contact us.