global: fix failing tests

- fix docs_require in setup.py
- fix import of EncryptedType in models.py, alembic recipe
6 jobs for 36-fix-failing-tests in 20 minutes and 59 seconds (queued for 6 seconds)
Status Name Job ID Coverage
  Test
passed py3.5-min-mysql #7871

00:09:16

92.0%
passed py3.5-min-postgresql #7869

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92.0%
passed py3.5-min-sqlite #7867

00:07:24

91.0%
passed py3.5-pypi-mysql #7872

00:09:46

92.0%
passed py3.5-pypi-postgresql #7870

00:04:44

92.0%
passed py3.5-pypi-sqlite #7868

00:06:47

91.0%