BZ 1097921 - first attempt at relaxing agent version check

This will allow the server to allow agents to connect to it, even if the agent versions don't match the exact server version (that is, we are now allowing the "prime directive" to be violated).

To supply the server with "supported agent versions", the build infrastructure needs to put "supportedAgentVersions" regex in the Product Info .properties file (this is already being generated, we just need to optionally add supportedAgentVersions - if it doesn't exist, the prime directive remains in force).

Note that no matter what, we no longer look at the build number of the agent to check its acceptability - build numbers are now irrelevant. Only the version string is being checked.