Dataviews code moved to the 'dataviews' experimental branch
Defined orientationsurround of OrientationContrast stimulus relative to the center orientation
TimeDependentValue generalized by returning value generated by time_fn
Merge pull request #17 from mjabri/master

Added NumpyFile array reader and associated tests on scale and offset in PatternGenerator that allow bit-for-bit copies of a specified Numpy array (or any other supplied pattern, such as an image, that doesn't need scaling).
Added boolean to select relative or absolute surround grating orientation in OrientationContrast
Cleaned up documentation and comments, and moved parameter setting from NumpyFile's constructor to a parameter declaration
Merge branch 'master' of https://github.com/ioam/imagen