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- changed copyright notice from "Christopher Simpkins" to "Source Foundry Authors"
- eliminated Python 2 interpreter support
- updated shebang lines to `!/usr/bin/env python3`
- black formatting for source files
- refactored Travis CI settings file
- modified Travis CI testing to Python 3.5 - 3.7
- refactored Appveyor CI settings file
- modified Appveyor CI testing to Python 3.5 - 3.7
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- removed unused variables in commands module
- add docs/LICENSE.md to release archives and Python wheels
- remove Pipfile and Pipfile.lock from version control

- initial stable/production release

- bug fix for report failures when the xHeight and CapHeight values are missing from OpenType OS/2 tables in some fonts

- added [OS/2] CapHeight metric to report table
- added [OS/2] xHeight metric to report table
- modified version string parsing for report to support fonts that do not contain langID=0 tables
- added release.sh shell script
- updated Travis CI testing settings
- updated Appveyor CI testing settings
- updated tox.ini Python tox testing settings

- minor Python style fixes (PR 8 by moyogo)