Change windows build slave to only do 1 build at a time.

git-svn-id: http://svn.wxwidgets.org/svn/wx/wxPython@76018 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Convert docset plist files back to textual XML.
Add note about compatibility

git-svn-id: http://svn.wxwidgets.org/svn/wx/wxPython@76019 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
PR 68: update unit tests for pubsub

git-svn-id: http://svn.wxwidgets.org/svn/wx/wxPython@76020 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Make the pubsub tests Py3 compatible

git-svn-id: http://svn.wxwidgets.org/svn/wx/wxPython@76021 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775