ACCUMULO-4361 Configure ShellServerIT to run with one tserver

[joshelser]

Refactored SharedMiniClusterIT a little bit to work around the
static initialization of the MAC which previously would not have
allowed tests to control how MAC is configured. This has the downside
of forcing new tests to remember to define BeforeClass and AfterClass
annotated methods which call the corresponding methods on SharedMiniClusterIT.

[joshelser]

Ran all unit tests and the following ITs (a list I found that would be affected by the change to SharedMiniClusterIT): ArbitraryTablePropertiesIT,CreateTableWithNewTableConfigIT,ShellServerIT,SplitCancelsMajCIT,CleanUpIT,DeletedTablesDontFlushIT,TabletStateChangeIteratorIT,T*ProxyIT,StatusCombinerMacIT

[keith-turner]

Ran all unit tests and the following ITs

Did you run findbugs, checkstyle, etc?

[keith-turner]

The changes look good. I can't think of a simpler way than making each subclass implement the before and after methods. Looked into the behavior of @BeforeClass and junit seems to always call the @BeforeClass method in the superclass 1st.

[joshelser]

Did you run findbugs, checkstyle, etc?

Yup

The changes look good. I can't think of a simpler way than making each subclass implement the before and after methods

Thanks for giving it a look! I'll work on merging this through.

[mjwall]

Thanks for this @joshelser