Implement test suite for org.opends.server.util.StaticUtils and make the following changes to the class:

* fix issue #685 (StaticUtils.charsToBytes incorrectly encodes non-ascii characters)

* rename charsToBytes to getBytes for consistency with getBytes(String)

* fix potential NPE in bytesToHex

* modified listsAreEqual so that it handles all types of List and falls back to default List.equals() implementation if the provided lists are not random access

* removed setsDiffer and replaced references to it with calls to Set.equals()