RFR: 8213222: remove RMIConnectorServer.CREDENTIAL_TYPES

[Daniil Titov]

Please review a change [1] that removes constant javax.management.remote.rmi.RMIConnectorServer.CREDENTIAL_TYPE. 
This constant represents the name of the attribute that specifies a list of class names acceptable to the RMIServer.newClient()
remote method call. This constant was superseded by RMIConnectorServer.CREDENTIALS_FILTER_PATTERN and marked as
deprecated for removal in JDK 10 [3].

A new CRS [4]  and a release note sub-task [5]  were also created. Please review the CSR [4] as well.

Text search over the repository didn't find any other usage of this constant. Tier1 - tier3 Mach5 tests succeeded.

[1] Webrev:  http://cr.openjdk.java.net/~dtitov/8213222/webrev.01/ 
[2] Issue: https://bugs.openjdk.java.net/browse/JDK-8213222 
[3] https://bugs.openjdk.java.net/browse/JDK-8191313 
[4] CSR:  https://bugs.openjdk.java.net/browse/JDK-8236954
[5] Release Note sub-task: https://bugs.openjdk.java.net/browse/JDK-8236955 

Thank you,
Daniil