[LDAP API] encoding refactoring status, 2

[Emmanuel Lécharny]

Hi !

I'm done with controls, and I'm currently adding tests for messages that 
have controls to check they all are properly handled. In the process, I 
have found *many* errors (like some controls that are simply nit working 
at all, not being able to be decoded...)

The next step will be the extended operations, then the intermediate 
operation (we have only one).

Once done, I'll be able to phase out the existing encoder to use the 
reverse one.

I hope to be done with this by the end of this week. When done, the next 
big step will be the removal of decorator.

More to come....