HBASE-12177 TestIPv6NIOServerSocketChannel hangs consistently on Java 8

Disable hanging tests on Java 8 for investigation
HBASE-12011 Add namespace column during display of user tables (Srikanth Srungarapu)
Revert "HBASE-12177 TestIPv6NIOServerSocketChannel hangs consistently on Java 8"

This reverts commit 7f8a86441ed9177498a7e73b2815055fd5271b54.

Further investigation indicates this is an OS or JVM issue on the
test host
HBASE-11890 HBase REST Client is hard coded to http protocol