Merged hotfix from v0.11.0a. Squashed commit of the following:

commit 27f214ac
Author: Paul McCarthy <pauld.mccarthy@gmail.com>
Date:   Wed Apr 26 18:20:08 2017 +0100

    Version bump

commit 52f759f0
Author: Paul McCarthy <pauld.mccarthy@gmail.com>
Date:   Wed Apr 26 18:05:11 2017 +0100

    More robust unit tests for async.idle(alwaysQueue=True). Also using a single
    wx.App object for complex reasons

commit d87aae89
Author: Paul McCarthy <pauld.mccarthy@gmail.com>
Date:   Wed Apr 26 18:00:13 2017 +0100

    Adjustment to async.idle(alwaysQueue=True) - now, a second idle call is only
    necessary if the first call came before a wx.App had been created.