chore(requirements): update pyldap to v2.4.35

[mboersma]

From the CHANGES doc at https://github.com/pyldap/pyldap/blob/master/CHANGES:

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Released 2.4.35 2017-04-25 (upstream)

Changes since 2.4.33: (2.4.34 is missing because of foolish pypi version madness)

Modules/

• use errno in a safer way
• set errno as LDAPError class item
• do not use strerror() which is not thread-safe and platform-specific

Lib/

• LDAPObject._ldap_call() sets LDAPError info to value returned by platform-neutral os.stderror()

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Released 2.4.33 2017-04-25 (upstream)

Lib/

• faster implementation of ldap.schema.tokenizer.split_tokens() (thanks to Christian Heimes)
• removed unused 2nd argument of ldap.schema.tokenizer.split_tokens()
• fixed method calls in ReconnectLDAPObject (thanks to Philipp Hahn)

Modules/

• an empty info message is replaced with strerror(errno) if errno is non-zero which gives more information e.g. in case of ldap.SERVER_DOWN (thanks to Markus Klein)
• removed superfluous ldap_memfree(error) from LDAPerror() (thanks to Markus Klein)

Tests/

• re-factored t_ldap_schema_tokenizer.py

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Released 2.4.32 2017-02-14 (upstream)

Running tests made easier:

• python setup.py test
• added tox.ini

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Released 2.4.31 2017-02-14 (upstream)

Changes since 2.4.30:

Tests/

• new test scripts t_ldap_schema_tokenizer.py and t_ldap_modlist.py on former raw scripts (thanks to Petr Viktorin)
• new test-cases in t_ldapurl.py based on former raw scripts (thanks to Petr Viktorin)
• new test-cases in t_ldap_dn.py
• moved a script to Demo/

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Released 2.4.30 2017-02-08 (upstream)

Changes since 2.4.29:

Lib/

• compability fix in ldap.controls.deref to be compatible to recent pyasn1 0.2.x (thanks to Ilya Etingof)

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Released 2.4.29 2017-01-25 (upstream)

Changes since 2.4.28:

Modules/

• Fixed checking for empty server error message (thanks to Bradley Baetz)
• Fixed releasing GIL when calling ldap_start_tls_s() (thanks to Lars Munch)