Removed explicit start of SuSEfirewall2 phase 2.

Reasons:
1) assumption stated in removed comment (... initial script is started
...) is not true in systemd world
2) as consequence of further operations, firewall in freshly installed
system is left in state as configured by SuSEfirewall phase 1. It is
because of service dependencies.
Updated changelog
Merge pull request #94 from mchf/openSUSE-13_1

Removed explicit start of SuSEfirewall's second phase