Update the agenda announcement and registration to the new dates
add the initial sponsors
add redgate to the sponsors
Add details of how to get to the venue by different means
remove unused images
update the carousel images

Fix typo
refactor some tests to introduce a builder pattern
add more instructions and a link to a useful app
make the links to the team images use Url.Content
refactor the loading of a conference out into a single place
prevent a list of sessions being loaded when it is not valid to see them

We do still want to link to individual sessions, but not show the whole
list
prevent a list of speakers being loaded when it is not valid to see them

We do still want to link to individual speakers, but not show the whole list
switch to the built in method for 404s
null check
prevent unauthorised editing of items
Prevent users from editing other users' profiles + tests
add some tests to check that the complete list of speakers and sessions cannot be seen when not appropriate
add more tests to confirm that actions cannot be performed on sessions of other users
update the conference code for the 2014 event
get the dates in the sidebar from the database