Merge pull request #136 from nperron/ust_3627/dev/3631_add_rudder_stdlib.st_in_the_inputs_list_of_CFE

Fixes #3631 - Modify policies/system/common/1.0/policy.xml to add rudder_stdlib.st in the inputs list of CFE generated by Rudder
Fixes #3604 - Add module to add configuration line in order to prevent rsyslog from dropping messages
Refs #3604 - Change name from rsyslog_not_older_than_5_7_1 to to rsyslog_greater_than_5_7_1, edit rsyslog.d/rudder.conf instead of rsyslog.conf and add an error message if the module used is missing
Refs #3604 - Use /etc/rsyslog.d/remove_limit.conf instead of /etc/rsyslog.d/rudder.conf for adding the config line, use body rudder_common_classes instead of cf2_if_else and prevent from checking presence of check_rsyslog_version_present if rsyslog is not used on the machine