EPICS-SNMP module from NSCL https://groups.nscl.msu.edu/controls/files/devSnmp.html with local modifications for use on WIN32

Original source code is on vendor branch

For usage docs see https://groups.nscl.msu.edu/controls/files/devSnmp.html

For WIN32 builds you will likely need to use our local changes to net-snmp in https://github.com/ISISComputingGroup/NET-SNMP