TEST visual.bufferimage.py

- 90% coverage, but almost no testing of actual function
- miss coverage for useShaders = False
TEST:  test_web (new under test_misc/)

- get 68% coverage if have internet access; skip tests if no internet access
BF: _getRegionOfFrame in pygame; closes #392
BF: benchmark wizard was skipping CPU speed test on windows
Merge pull request #391 from jeremygray/master

more test coverage, _getRegionOfFrame fix