Look into alternative Embedded LDAP solutions

[rwinch]

ApacheDS struggles with passivity. For example, updating to a point release should not cause non-passive changes as demonstrated in #30

Furthermore, Support has been dropped for ApacheDS 1.x, but Apache DS is still in milestone. While there have been many releases of ApacheDS 2.x, it has been in milestone for nearly 5 years (since June of 2011).

We should look into alternative embedded LDAP instances.

A few resources from StackOverflow

• http://www.opends.org/
• http://www.unboundid.com/products/ldap-sdk/
• http://ff1959.wordpress.com/2011/11/01/ldap-in-memory-directory-server-using-unboundid-ldap-sdk/

[eddumelendez]

Currently, I am working on this. Got some troubles running tests in spring-ldap-test-unboundid. If anyone want to help please check this commit https://github.com/eddumelendez/spring-ldap/commit/4e98ecefc6c2a82110d07a14608686212143bf2c

[eddumelendez]

@rwinch PR submitted