fix configuration

adding methods add_user and del_user ...

* adding add_user
* adding del_user
* adding unit tests
* adding configuration parameters for adding users

adding objectclasses options

implementing search users ...

* adding search
* adding unit tests

adding search template

multiple changes ...

* implemeting recover user attributes
* adding a unit test for unavailable ldap
* adding a parameter timeout to set the ldap timeout connexion

many fixes in unit tests + fix in params + fix in constant ...

Oh god, python-ldap is crap...
* add better unit test
* correct params name
* correct exception handling
* disable testConnectSSLNoCheck (impossible to test with a certificate
  previously defined)

multiple changes ...

* change parameters name for Backend Ldap
* fix default value handling in backends get_param
* correct exception in backends get_param
* fix syntaxe error
* add backend name in test_BackendLdap.py

fix backend name

implementing loading backends ...

* fix conf file
* add exceptions
* fix modules skeletons

set log level to debug for test configuration

adding loading roles and attributes

begin implementation of the main application