OPENDJ-1368 (CR-3157) Remove AttributeValue

Removing AttributeValue.getNormalizedValue().
Converted from AttributeValue.getNormalizedValue() to MatchingRule.getAssertion() OR MatchingRule.normalizeAttributeValue() + AttributeValue.getValue().

PatternRDN.java:
In matchValuePattern(), reversed if statement for better readability.

*.java:
Did not normalize values passed into DN.decode(ByteString) because DN class knows how to normalize itself when needed.
Fixed several places that used normalizeAttributeValue() to normalize assertions.
Fixed several places that used EqualityMatchingRule.normalizeAttributeValue() instead of OrderingMatchingRule.normalizeAttributeValue().