Fix build task for concrete5 5.7

Fixes #689
Fix too much cleanup
Remove formatting by getDate... methods

Some (but not all) of the model methods that return a date/time try to
format the timestamp and to handle the timezone.
Let's keep this in a central place (the DateHelper)
Increase the install timeout
Translate topics.js
Better JavaScript styling ;)
Use the concrete5 date/time control in Preview as user

The standard concrete5 date/time control takes in account user timezone
and is locale-aware.
Localize thumbnail type names
Fix the Facebook association email

Fix some typo
Merge branch 'fix-grunt-build-task' of https://github.com/mlocati/concrete5-5.7.0 into mlocati-fix-grunt-build-task
Merge pull request #698 from mlocati/increase-install-timeout

Increase the install timeout
tweak to composer
Merge branch 'mlocati-fix-grunt-build-task'
Merge branch 'master' of github.com:concrete5/concrete5-5.7.0
gradual toolbar loaders
Merge pull request #704 from mlocati/typo-in-facebook-activation-email

Fix the Facebook association email
Merge pull request #697 from mlocati/date-formatting-only-in-helper-v2

Remove formatting by getDate... methods
Merge branch 'master' of github.com:concrete5/concrete5-5.7.0
Merge pull request #699 from mlocati/translate-topics-stuff

Translate topics.js
Merge branch 'master' of github.com:concrete5/concrete5-5.7.0