Retrieves the implementation version of the AJAPI release that this Server class is from.
This is the same as the version of the Agentry Server that the AJAPI JAR file came with.
This information is retrieved from the AJAPI JAR manifest file via the Package class.
Note that this does not necessarily reflect the version of the API that this JAR implements; for example, if this JAR implements version 4 of the AJAPI, but it comes with version 5.0.0.3 of the Agentry server, this will return 5.0.0.3, not 4! If you want to know the AJAPI version that is implemented, call getSpecificationVersion() instead.