[feature, 1.4.4] Allow to specify directory in Include directive in agent

[Shmuma]

Hello,

We use debian packages to distribute zabbix config files with user checks which included in main agent config file. Currently, all included files must be specified explicitly which is too boring and can lead to errors.

This patch allows to specify directory name in Include directive. All files from this directory are included into config file.

This approach is similiar to /etc/cron.daily/ or /etc/rcN.d/

For example:

Include=/etc/zabbix/user1.conf
Include=/etc/zabbix/conf.d/

In the above example, user1.conf and all files from conf.d will be parsed on agent startup.

This patch is against 1.4.4

[Sasha]

Thank you!
Your patch is integrated in Zabbix 1.5 revision 5742.