The images from OpenStreetMap take a while to load, sometimes even
causing Net::ReadTimeout errors if the internet connection is slow. It's
happened a lot recently on Travis builds.
Using capybara-webmock we guarantee the test suite doesn't fail due to
network issues.
We were having problems under certain conditions with Travis and
Knapsack where tasks were still being loaded twice and so they were
being executed twice.
Calling `load_tasks` in several files made rails load the tasks several
times, and so they were executed several times when called.
Since the milestone migration can't be executed twice in a row (it would
fail with duplicated ID records), loading the tasks several times made
the milestone migrations task specs fail.
We were seeing a log message when running specs locally
```
[Coveralls] Set up the SimpleCov formatter.
[Coveralls] Using SimpleCov's 'rails' settings.
```
As Coveralls is mainly used in Travis CI, we do not need to load it in
every spec run
