[syslog-ng] include branch merged

Hi, After the release of syslog-ng OSE 3.0.1, I merged include file support to mainline. It is already pushed to the git repository, but also should be in tomorrow's snapshot. The syntax is: include "file-or-directory-to-be-included"; If you specify a directory, syslog-ng is going to include the files in alphabetical order. The same rules apply to as to run-parts(8). -- Bazsi