1.3.1dev: Remove appveyor Python 2.6 configurations from matrix
1.3.1dev: Remove appveyor Python 2.6 configurations from matrix

Refs #11901, #12120.


git-svn-id: 0d96b0c1a6983ccc08b3732614f4d6bfcf9cbb42@14896 af82e41b-90c4-0310-8c96-b1721e28e2e2

rbaumg/trac,rbaumg/trac,rbaumg/trac,rbaumg/trac