Merge pull request #2 from redealumni/upgrade_rails_4

Upgrade to Rails 4
Merge pull request #3 from redealumni/fixes_improvements

General fixes and improvements
Adding separate listings for hidden users

Changes the index page of the User model to show two separate tables:
one for the normal users and one for the hidden ones.
Cleaning test files

Still not passing, but now following Rails 4 conventions.

One day we shall make them pass.
Add hide user option for admin screen

Allows to hide users directly from the user listing screen.

Also improved some text from the views.
Adding automatic fixing of punches

New PunchMaintenance module, which check for holes and add
commented punches. Two ways to use it were added:
- A cron job (using Whenever) which runs everyday at 1 am
fixing the punchs from yesterday
- A Rake task maintenance:fix_punches which fixes all punches in
the database. A maintenance:validate_punches task was also added

Some related changes, all non-destructive
- A change to the Punch model, namely how the before_save callback
is set, to use a private method instead of a block
- A IterationHelper module with a custom iterator for dealing
with checking the punches
- db/seeds.rb changed to add a bunch of random data to the database
for testing - only in development environment
Merge branch 'async_fix_punches' of https://github.com/redealumni/bate_ponto into async_fix_punches