bash completion script

Signed-off-by: Alexandre Almeida Barbosa <alexandrealmeidabarbosa@gmail.com>
Signed-off-by: Athos Ribeiro <athosxd@gmail.com>
Signed-off-by: Kamilla Crozara <holanda.kamilla@gmail.com>
Signed-off-by: Tiago Pereira <tiagogomespereira@gmail.com>
Complete most commands with directory names

Signed-off-by: Antonio Terceiro <terceiro@softwarelivre.org>
Signed-off-by: Paulo Meirelles <paulo@softwarelivre.org>