ACCUMULO-3220 Fail fast if the provided cipher isn't a block cipher.
Merge branch '1.6'
ACCUMULO-3221 Ensure arithmetic happens as longs and not integers.
Merge branch '1.5' into 1.6

Conflicts:
	core/src/main/java/org/apache/accumulo/core/util/shell/Shell.java
Merge branch '1.6'
ACCUMULO-3220 Make sure to re-set the local cipher variable when it wasn't initialized
Merge branch '1.6'
ACCUMULO-3215 Remove deprecated javadoc link

  Remove unneeded javadoc link to deprecated property in a test to avoid a
  deprecation warning.
Merge branch '1.6'
ACCUMULO-3222 Get Durability for tablet after null check. Add final modifiers.
ACCUMULO-3218 Set the list separator to \0 to 'disable' list interpretation

ZooKeeperInstance, because of how commons-configuration was parsing the
values, was treating a comma separated list of ZK servers (which
we intend to be a single value) as multiple and only returning
the first when getString was called on its key. We have no case
where we actually want values to be automatically parsed into an
array, so we can set it to a separator highly unlikely to be used.
ACCUMULO-3223 Explicitly handle null from getOnlineTabletsForTable
Merge branch '1.6'

Conflicts:
	core/src/test/java/org/apache/accumulo/core/client/ZooKeeperInstanceTest.java
Merge branch '1.5' into 1.6
Merge branch '1.6'