Cperello/distribution groups modification fixes

	Standalone basic users operations Test Suite
		EnableUsersZentyalTest: OK
		AddUser: OK
		CheckUSer: OK
		AddGroup: OK
		AddUserToGroup: OK
		CheckGroup: OK
		DelUser: OK
		CheckDeletedUser: OK
		AddOU: OK
		AddUserToOU: OK
		CheckUser: OK
		CheckSSHLoginWithoutPAM: OK
		EnablePAM: OK
		CheckSSHLoginWithPAM: OK
		AddDistributionGroup: OK
		EditDistributionGroup: OK
		ChangeDistributionGroupType: OK
		AddSecurityGroup: OK
		EditSecurityGroup: OK
		ChangeSecurityGroupType: OK
		check-zentyal-log: OK
		check-syslog-apparmor: OK