\SMW\HashIdGenerator (separate responsibility)

\SMW\HashIdGenerator
Code coverage: 100%
CRAP: 3

\SMW\CacheIdGenerator
Code coverage: 100%
CRAP: 4

* CacheIdGenerator extends HashIdGenerator
* To be used in Subobject::getAnonymousIdentifier to replace
hash( md4 )

Change-Id: Ife6d87174ed68d35df7e1f70ca6b4067fde0917b