A start on improving the events page
Nowhere near complete: I plan to introduce a calendar and "My events" pages in the near future, and fix the face that we pretty much duplicate the front page (I have a plan...). But, I think I should incrementally make changes as to gather feedback from others
Remove additional search box
Added 404 template and handling for when an event is not found from its stub
Merge branch 'events-sorting' of github.com:clairs/joindin-web2 into pr108
Add pagination
Upcoming events is a good choice of filter.
Merge branch 'pr108'
Merge branch 'event_404' of github.com:dstockto/joindin-web2 into pr111
Consistent casing in titles
Fix route name when trying to redirect to /event
Merge branch 'pr111'
Remove Slim 1.x
Add Slim 2.4.2
Minor PSR-2 format fiix.
Update to latest Twig view for Slim

Note that it's modified from the original by removing the Slim\Views namespace and renaming the class to TwigView.
Add Slim's autoloader
Slim is now within the Slim namespace.
Code coverage shows test folder and not app

The whitelisting of the code coverage was set to only show the coverage of
the test folder itself; which unsurpisingly was almost 100%. By changing the
whitelist to point to the app folder in the root of the project we get an
accurate representation of the code coverage.

After running the unit tests one can see the code coverage in the
build/coverage folder; by opening the index.html you can browse through all
files and determine what needs to be covered.
Remove superfluous and misleading echo's

In the each call to render seems to be prefixed with the echo keyword
but the render method does not return data; it adds the rendered output
to the view cache / output buffer so that it can be echo'd later
by Slim itself.

In this commit I remove all superfluous echo's since it may mislead
people into thinking that the echo's actually have a function and use
it to circumvent the view mechanism of Slim or have unpredictable bugs.
Added a Composer file with license

With this commit we add the composer.json and lock file together
with a license file indicating that this project is under the
MIT license (discussed with @akrabat to be sure).

In addition to the above I have prevented the .git folder in the
vendor folder from being committed.

The vendor folder itself will be submitted in a separate commit
to make it easier for a code reviewer to see which changes are
the onces actually needing a review.