Freetype-py

* Remove Python 3.7 CI builds, we don't actually need them.

* Update bundled FreeType to 2.10.0
* Update bundled HarfBuzz to 2.3.1
* Add Python 3.7 builds to PyPI
* Removed `FT_Outline_{New,Done}_Internal` functions, as these were only accidentally exposed in the public API.
* `FT_Face` can now be instantiated with a file path or a byte stream from memory
* Fix bug where outline and bitmap could be off by one grid unit in one of the examples, when extrema did not have on-curve points.
* Corrected the license classifier, the project is BSD licensed.

Take five.

Take four.

Fix AppVeyor deploy, take three.

Fix what post2 should have fixed (hopefully).