General bug fixes.

These twelve patches should apply to the master branch. They include:

* Option to prevent child processes from respawning.
* Remove duplicate code for command-line option processing.
* Updated usage message that uses poptPrintUsage.
* Updated man page for keepalived(8).
* Fix pointer arithmetic in vrrp_in_chk() when IPSEC AH is enabled.
* Fix loading of SSL certificate.
* Fix typo in error messages.
* Update GPLv2 license in COPYING file.
* Fix byte-ordering for comparing primary IP address.
* Remove log_message calls from if_get_by_ifname.
* Fix macro in keepalived.conf.5 man page.
* Add To header for SMTP alerts.

Feedback always appreciated.