db_ido: Add idoutils 1.x schema, check required 1.10.0 version.

fixes #4766
Fix ITL attributes.
Update duration literal documentation.
ExternalCommandListener: Reset umask to preserve group write permissions.

refs #4444
LivestatusListener: Set unix socket permissions to 0660.

refs #4444
Install /var/run/icinga2/rw command mode, add configure options.

- changed locations for icinga2.cmd and livestatus unix socket
- make install creates /var/run/icinga2/rw and sets g+s for
  icinga:icingacmd
- configure options: --with-icinga[cmd]-{user,group}=
- add autoconf macros to check user/group and bail early if not created
- update documentation/INSTALL

fixes #4444
refs #3186
Fix error message.
Replace umask() with chmod() because it's not thread-safe.
Fix: ACICINGA_CHECK_USER doesn't work on OS X or when using NIS.
Revamp livestatus startup logging a bit.
Update documentation.
Remove unused files.
configure: Show users/groups.
Fix: make dist-* does not include lib/config/config_parser.h

Fixes #3575
Build fix.
Set proper user/group for config files.
Rename directory for Icinga socket files.
Add more feature config files.
Add another feature config file.
Implement validator for LivestatusListener::socket_type.

Fixes #4751