Added import forgotten from previous commit
Fix a possible EINTR problem in dviread
Clarify hist docstring
fixed from_images to respect stride
commited jae joons 2nd patch; figimage still sems broken for origin=up
added jae joons layer images patch
Fix bugs in unit-handling in axhspan and axvspan
Improve error reporting when pygtk or gtk+ headers are missing.
add docstring for mmap NetCDFFile keyword.
