Update psycopg2 to 2.8

[pyup-bot]

This PR updates psycopg2 from 2.7.7 to 2.8.

Changelog

2.8

-------------------------

New features:

- Added `~psycopg2.errors` module. Every PostgreSQL error is converted into
a specific exception class (:ticket:`682`).
- Added `~psycopg2.extensions.encrypt_password()` function (:ticket:`576`).
- Added `~psycopg2.extensions.BYTES` adapter to manage databases with mixed
encodings on Python 3 (:ticket:`835`).
- Added `~psycopg2.extensions.Column.table_oid` and
`~psycopg2.extensions.Column.table_column` attributes on `cursor.description`
items (:ticket:`661`).
- Added `connection.info` object to retrieve various PostgreSQL connection
information (:ticket:`726`).
- Added `~connection.get_native_connection()` to expose the raw ``PGconn``
structure to C extensions via Capsule (:ticket:`782`).
- Added `~connection.pgconn_ptr` and `~cursor.pgresult_ptr` to expose raw
C structures to Python and interact with libpq via ctypes (:ticket:`782`).
- `~psycopg2.sql.Identifier` can represent qualified names in SQL composition
(:ticket:`732`).
- Added `!ReplicationCursor`.\ `~psycopg2.extras.ReplicationCursor.wal_end`
attribute (:ticket:`800`).
- Added *fetch* parameter to `~psycopg2.extras.execute_values()` function
(:ticket:`813`).
- `!str()` on `~psycopg2.extras.Range` produces a human-readable representation
(:ticket:`773`).
- `~psycopg2.extras.DictCursor` and `~psycopg2.extras.RealDictCursor` rows
maintain columns order (:ticket:`177`).
- Added `~psycopg2.extensions.Diagnostics.severity_nonlocalized` attribute on
the `~psycopg2.extensions.Diagnostics` object (:ticket:`783`).
- More efficient `~psycopg2.extras.NamedTupleCursor` (:ticket:`838`).

Bug fixes:

- Fixed connections occasionally broken by the unrelated use of the
multiprocessing module (:ticket:`829`).
- Fixed async communication blocking if results are returned in different
chunks, e.g. with notices interspersed to the results (:ticket:`856`).
- Fixed adaptation of numeric subclasses such as `~enum.IntEnum`
(:ticket:`591`).

Other changes:

- Dropped support for Python 2.6, 3.2, 3.3.
- Dropped `psycopg1` module.
- Dropped deprecated `!register_tstz_w_secs()` (was previously a no-op).
- Dropped deprecated `!PersistentConnectionPool`. This pool class was mostly
designed to interact with Zope. Use `!ZPsycopgDA.pool` instead.
- Binary packages no longer installed by default. The 'psycopg2-binary'
package must be used explicitly.
- Dropped `!PSYCOPG_DISPLAY_SIZE` build parameter.
- Dropped support for mxDateTime as the default date and time adapter.
mxDatetime support continues to be available as an alternative to Python's
builtin datetime.
- No longer use 2to3 during installation for Python 2 & 3 compatibility. All
source files are now compatible with Python 2 & 3 as is.
- The `!psycopg2.test` package is no longer installed by ``python setup.py
install``.
- Wheel package compiled against OpenSSL 1.0.2r and PostgreSQL 11.2 libpq.

Links

• PyPI: https://pypi.org/project/psycopg2
• Changelog: https://pyup.io/changelogs/psycopg2/
• Homepage: http://initd.org/psycopg/

[codecov-io]

Codecov Report

Merging #888 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #888   +/-   ##
=======================================
  Coverage   73.52%   73.52%           
=======================================
  Files         108      108           
  Lines        4733     4733           
  Branches      605      605           
=======================================
  Hits         3480     3480           
+ Misses       1031     1030    -1     
- Partials      222      223    +1

Impacted Files	Coverage Δ
tcms/core/history.py	90.69% <0%> (ø)	⬆️

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[coveralls]

Pull Request Test Coverage Report for Build 2927

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 74.187%

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Totals
Change from base Build 2924:	0.0%
Covered Lines:	3702
Relevant Lines:	4733

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💛 - Coveralls