The Coding 40 group members write their programs together. So, this
code is a result from work.

pev main author is Fernando Mercs <fernando@mentebinaria.com.br>

Coding 40 group members:

Eduardo Fernandes <eduardoffs@gmail.com>
Francivan Bezerra <fba.rio@gmail.com>
Gustavo Mahler <gustavo9035@hotmail.com>
Thiago Moraes <moraes73@gmail.com>

Thanks to Evan Teran <eteran@alum.rit.edu> and
Gabriel Duarte <confusosk8@gmail.com> for help.
