Leo 6.4 created. devel is now open and contains the basis for 6.5

[Edward K. Ream]

Leo 6.4 (final) now exists here, on GitHub This release will be the basis of the pypi (pip install) version of Leo.

I'll announce 6.4 on Wednesday after creating the pypi distro.

The devel branch now contains the basis of Leo's 6.5 code base, per #1766:

- `@test`, `@suite`, unitTest.leo, and leoTest.py are gone.  Hurray.

- leoTest2.py contains straightforward utilities for traditional unit tests.

- The leo/unittests folder contains all of Leo's unit tests.

- None of Leo's files (including leoAst.py) contain any test code.

- The leo/test directory has been thoroughly cleaned.

Summary

Leo 6.4 is here. I'll announce it Wednesday, after creating the pypi distro.

The devel branch now contains the foundation of Leo's 6.5 code base, including an all-new unit-testing framework.  `@test`, `@suite` and unitTest.leo no longer exist.

The test-all command runs all of Leo's unit tests. 

Edward