Cleaned up init code.

There was lot of clutter and misleading comments in the code
and some minor coding convention issues. This patch cleans up
init.c for the most part.
(cherry picked from commit c59864f9d4a67dcf76ba01d9c4db2b12fada6339)
libsmack: clean up smack_accesses_add_modify()

This patch makes smack_accesses_add_modify() easier to follow by
changing variable names bit more self-documentative and less easier
to mix up with adding and deleting rules. This patch also fixes some
very minor coding style errors.

Also documentation of this function is cleaned up.
(cherry picked from commit 22c98dd03e352057b23f8d8d2d9ad252175c685b)
Fixes for doxygen errors coming from 3810596.

Doxygen errors that are regression from 3810596. Went in because
I forgot to install doxygen into my test environment.
(cherry picked from commit 8ef1846c05d32a92b23538ee491fd31350c2a045)
Documented order in which access rules are applied to kernel.
(cherry picked from commit f82cadf3b7a9d84ae0bf2aa06fb8ecff9b4332dc)
Fix: allow CIPSO labels with zero categories

There was false restriction in smack_cipso_add_from_file() that
disallowed CIPSO labels without categories.

For example, this example given in the SMACK kernel documentation
should be perfectly legal:

TopSecret 7
(cherry picked from commit 4e4ea9142727ca7f14bf1d64cd81949b28bb1d0b)
Change apply_cipso_cb() to use proper apply_cipso_file()

apply_cipso_cb() used improper apply_rules_file(). Changed this to
call apply_cipso_file() instead.
(cherry picked from commit d45ffe9082243377cdba9a2d224bab0e110501e0)