fix authentification for AD backend

more encoding error fix (on ldap auth)

more encoding fixes

fix more encoding error

fix rename in modify ...

when renaming an entry, dn must be reset to the correct value for
the modifications that come after the rename.

many fixes in encoding handling

removing utf-8 crap in AD backend ...

the crap must be fixed in LDAP backend first

fix encoding error on dn

fix pep8 compliance

typo + add/del group in AD backend ...

* implementing add_to_group and del_from_group in AD backend.
* fixing typo self.objetclasses => self.objectclasses

making Backend skeleton a child class of object ...

this enables the use of super()

Better exception re-raising ...

re-raising the exception without specifying the exception object gives
exactly the previous exception (including the correct stacktrace)
which is nicer to have for debugging.

implementing renaming entry

fix recovery of groups in AD backend

adding filter for ad backend

fix search template for AD backend

fix unit tests

Merge branch 'master' of https://github.com/kakwa/ldapcherry

renaming and begining implementing the ad backend

fix docstring in ldapcherry/backend/__init__.py

add docstring for backend

escaping search string for ldap

better exception handling if user or group doesn't exist

pep8 compliance

pep8 compliance

many pep8 fixes thanks to pep8ify

remove trailing spaces

various fix on ssl/tls + tests ...

* making ssl cert check and cert no check works
* adding a test to check if the cafile does exist
* reenable and fix ssl checks on travis

better exception handling in ldap backend

fix unicode