Cnx-db

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- Merge pull request 194 from openstax/933-remove-transform-migration
- pin lint dependencies to versions that passed in last build of master
- setuptools>=45 breaks python 2.7 build for travis. Setting different
installs for setuptools for python 2 and 3
- added pip install -upgrade pip to .travis.yml file in before_install step
- Removed 20170911201035_transform_cnxml_to_html.py from migrations
- Merge pull request 193 from openstax/cnx-stack-compose
- Add script to create legacy user w/ passwd for dev purposes
- Accept explicit and multiple values for table unique key
- Attempt to not insert when a duplicate pkey is found
- Bump sequences to max pkey value to avoid conflicts
- Remove upload pypi step in Jenkinsfile (192)

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- Add twine check on travis (190)
- Separate db_tables function and fixture for reuse (191)

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- Rebake only latest openstax books in transforms migration (189)

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- Documentation for the database triggers (188)
- Rebake books in cnxml-to-html transforms migration (187)

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- Fix empty collated file associations in dump_book.py (185)
- Pin docutils to 0.14 in requirements/lint.txt (186)
- Repeat populate tree slug migration
- Add cache purging code to populate trees slug migration
- Update setup.py to require cnx-common>=1.2.1

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- Move ident-hash parsing functionality to cnx-common (180)
- Purge varnish cache after transforms (181)
- Add script/dump_book.py to dump/load a book from db (183)
- SQL queries for xpath search (182)