* Bump tensorflow from 1.14.0 to 1.15.0

Bumps [tensorflow](https://github.com/tensorflow/tensorflow) from 1.14.0 to 1.15.0.
- [Release notes](https://github.com/tensorflow/tensorflow/releases)
- [Changelog](https://github.com/tensorflow/tensorflow/blob/master/RELEASE.md)
- [Commits](https://github.com/tensorflow/tensorflow/compare/v1.14.0...v1.15.0

)

Signed-off-by: dependabot[bot] <support@github.com>

* bumps version of docker image from 3.6.9 to 3.6.10

* upgrades pip inside docker

* fixing astroid and pylint versions to avoid false positives

Co-authored-by: LSH <lsh-0@users.noreply.github.com>

* ugraded to python 3

* upgrade pylint and pytest

* replaced StandardError

* exclude useless-object-inheritance

* python3 compatibilities uncovered by linting

* fixed tests

* fixed more python3 test incompatibilities

* added dev-venv target

* added subextract model

* added nltk dependency

* flake8 ignore line break before binary operator

* moved dev dependencies up

* added nltk punkt download

* added nltk download to dev-venv; pytest and pytest-not-slow target

* added subextract training pipeline

* added optional xpath namespaces

* log failed xml file

* use recover parser option

* added subextract app

* start subextract server

* renamed to autocut

* declare slow and very_slow pytest markers

* make autocut main test as slow

* fixed post data

* updated README

* also build non-dev image as part of ci

* added pytest.ini to dev image

* added Makefile; optionally install dev requirements

* added ci-build-and-test

* use ci-build-and-test

* don't install dev dependencies as part of project_tests

* renamed to dev

* use PROJECT_FOLDER for consistency with other projects

* change order of tests run

* added pylint check

* added pylintrc to docker image

* reduced accessive apache beam debug logging

* configured pylint, addressed linting

* enabled flake8 checks

* downgrade pycodestyle to 2.3.1 due to error

* switch to 4 spaces indent

* autopep8

* more flake8

* added new line to .flake8

* Renamed files to be consistent with 'sciencebeam' repo

* Update Dockerfile and README after filename change

* Update version of tensorflow-transform to 0.6

* Pin versions of oauth2client and httplib2 to prevent errors with google-cloud. Update apache_beam to 2.4 as used by new version of tensorflow-transform

* upgrade Apache Beam version

* do not inherit MockFileSystem from LocalFileSystem

* upgraded dependencies

* added pylint to dependencies

* addressed np.fromstring warning

* select contributors without type or type author

* downgrade apache beam version