Editing documentation of module 'sigproc'.

Signed-off-by: Eduardo Tenorio <embatbr@gmail.com>
Editing Major Paper.

Signed-off-by: Eduardo Tenorio <embatbr@gmail.com>
Adding new reference.

Signed-off-by: Eduardo Tenorio <embatbr@gmail.com>
Last edtion of module 'sigproc_test'.

Signed-off-by: Eduardo Tenorio <embatbr@gmail.com>