Update pt_br.php

add security
Merge pull request #16 from JulioCF/patch-1

Update pt_br.php
Follow-up to 82b583b
- Changed calls on `global_reg_value` to char_reg_num_db` where appropriate.
- Additionally changed a comment in the application config which may be misinterpreted

Special thanks to ossi0110 for resolving the issue so quickly ( http://hercules.ws/board/topic/3996-fluxcp-for-new-sql-table/ ) and Emistry for pointing out the confusing implication in the application config.