Checkmk Werk 13574: Update net-snmp lib to 5.9.1

ID: 13574 Title: Update net-snmp lib to 5.9.1 Component: inline-snmp Level: 2 Class: Bug fix Version: 2.1.0i1 We now ship omd with the net-snmp lib in version 5.9.1. This was motivated by several reasons: * The previously used net-snmp lib had a bug in the python C binding which caused any higher auth protocol then SHA/MD5 not working. (e.g. SHA256, SHA512 etc.). This affected the inline SNMP mode in checkmk only. * The net-snmp project had a long time no releases. So we now want to go for the latest release.