[ELY-16] Adding ApacheDS to test suite.
[ELY-16] Add a SimpleDirContextFactory and builder, add test to verify connectivity using the test accounts.
[ELY-16] Add the mapNameToPrincipal implementation for LDAP.
[ELY-16] An additional set of tests for different options loading principals from LDAP.
[ELY-16] Adding support for clear passwords and trivial digest passwords.
[ELY-16] Add support for SSHA / Trivial salted digest password representations.
[ELY-16] Add support for {cryp} userPassword representations.