Merge pull request #522 from jeremygray/master

BF: allow 1-item conditions in conditions file import; closes #519
BF: better checking of graphics card before using FBO

Also removed duplicate check that FBO had worked
RF: reworking gamma value setting for monitors with gamma but no gammaGrid

This needs a py.test added to check for incorrect settings
Also needs an entry adding to __del__ to try and undo the setting
ENH: Fix ImportError if old wxpython is installed

Builder imports modules from wxpython 2.8 which are not available for
older versions. If the system had older versions installed and one of
these versions was set as the default than starting Builder raised an
ImportError. This was fixed by just using wxversion to ensure that at
least wxpython 2.8 is available which provides the needed agw module.
DOC: Fix two typos in documentation
Merge pull request #524 from philippwiesemann/fix-builder-minimal-wxpython

ENH: Fix ImportError if old wxpython is installed
BF: fix automated import of gamma for known monitors

In version 1.80.00 there was a bug for certain monitor objects due to
confusion between getGamm() and getGammaGrid()

Now getGammaGrid() takes preference, but getGamma() is used as fall-back and
tests have been added to the test suite to prevent any further regression
on this
ENH: added demo for CRS bits_sharp and a script to run getLumSeries from monitors
TESTS: prevent psychopy from setting hardware gamma table on virtual linux

this means we can run more tests on Travis-CI (just skipping the problem
line in the psychopy lib itself)
FF: last commit failed to import os but it was needed (sorry)
TESTS: more explicit test for the Travis environment than using xvfb
TESTS: fixes to testing under Travis