Update lxml to 4.3.3

[pyup-bot]

This PR updates lxml from 4.1.1 to 4.3.3.

Changelog

4.3.3

==================

Bugs fixed
----------

* Fix leak of output buffer and unclosed files in ``_XSLTResultTree.write_output()``.

4.3.2

==================

Bugs fixed
----------

* Crash in 4.3.1 when appending a child subtree with certain text nodes.

Other changes
-------------

* Built with Cython 0.29.6.

4.3.1

==================

Bugs fixed
----------

* LP1814522: Crash when appending a child subtree that contains unsubstituted
entity references.

Other changes
-------------

* Built with Cython 0.29.5.

4.3.0

==================

Features added
--------------

* The module ``lxml.sax`` is compiled using Cython in order to speed it up.

* GH267: ``lxml.sax.ElementTreeProducer`` now preserves the namespace prefixes.
If two prefixes point to the same URI, the first prefix in alphabetical order
is used.  Patch by Lennart Regebro.

* Updated ISO-Schematron implementation to 2013 version (now MIT licensed)
and the corresponding schema to the 2016 version (with optional "properties").

Other changes
-------------

* GH270, GH271: Support for Python 2.6 and 3.3 was removed.
Patch by hugovk.

* The minimum dependency versions were raised to libxml2 2.9.2 and libxslt 1.1.27,
which were released in 2014 and 2012 respectively.

* Built with Cython 0.29.2.

4.2.6

==================

Bugs fixed
----------

* LP1799755: Fix a DeprecationWarning in Py3.7+.

* Import warnings in Python 3.6+ were resolved.

4.2.5

==================

Bugs fixed
----------

* Javascript URLs that used URL escaping were not removed by the HTML cleaner.
Security problem found by Omar Eissa.  (CVE-2018-19787)

4.2.4

==================

Features added
--------------

* GH259: Allow using ``pkg-config`` for build configuration.
Patch by Patrick Griffis.

Bugs fixed
----------

* LP1773749, GH268: Crash when moving an element to another document with
``Element.insert()``.
Patch by Alexander Weggerle.

4.2.3

==================

Bugs fixed
----------

* Reverted GH265: lxml links against zlib as a shared library again.

4.2.2

==================

Bugs fixed
----------

* GH266: Fix sporadic crash during GC when parse-time schema validation is used
and the parser participates in a reference cycle.
Original patch by Julien Greard.

* GH265: lxml no longer links against zlib as a shared library, only on static builds.
Patch by Nehal J Wani.

4.2.1

==================

Bugs fixed
----------

* LP1755825: ``iterwalk()`` failed to return the 'start' event for the initial
element if a tag selector is used.

* LP1756314: Failure to import 4.2.0 into PyPy due to a missing library symbol.

* LP1727864, GH258: Add "-isysroot" linker option on MacOS as needed by XCode 9.

4.2.0

==================

Features added
--------------

* GH255: ``SelectElement.value`` returns more standard-compliant and
browser-like defaults for non-multi-selects.  If no option is selected, the
value of the first option is returned (instead of None).  If multiple options
are selected, the value of the last one is returned (instead of that of the
first one).  If no options are present (not standard-compliant)
``SelectElement.value`` still returns ``None``.

* GH261: The ``HTMLParser()`` now supports the ``huge_tree`` option.
Patch by stranac.

Bugs fixed
----------

* LP1551797: Some XSLT messages were not captured by the transform error log.

* LP1737825: Crash at shutdown after an interrupted iterparse run with XMLSchema
validation.

Other changes
-------------

Links

• PyPI: https://pypi.org/project/lxml
• Changelog: https://pyup.io/changelogs/lxml/
• Homepage: http://lxml.de/

[coveralls]

Coverage increased (+0.06%) to 30.441% when pulling d0564a5 on pyup-update-lxml-4.1.1-to-4.3.3 into 8613d9d on master.

[pyup-bot]

Closing this in favor of #301