Replace static methods with single getInstance

Replace static methods with single getInstance

Some of the PAP classes use a number of static methods.  These have
been modified to use regular, non-static methods, a single static
method, getInstance.
Also modified PapStatisticsManager so its methods are thread safe.
Changed "instance" to "current" for the activator, as it may be changed.
Fix new checkstyle issues.
Updated copyrights.
Renamed test class to be consistent.
Added test for getCurrent/setCurrent and isAlive.

Change-Id: Id6df55fa4c116852032ad61f80f899fcd292f864
Issue-ID: POLICY-1444
Signed-off-by: Jim Hahn <jrh3@att.com>