Remove devel/py-ctypes (only needed by and supporting python24).
Remove PYTHON_VERSIONS_ACCEPTED and PYTHON_VERSIONS_INCOMPATIBLE
lines that just mirror defaults now.
Miscellaneous cleanup while editing all these files.
Gwyddion is a modular program for Scanning Probe Microscopy (SPM) data
visualization and analysis. It is primarily intended for analysis of height
field data obtained by microscopy techniques like Atomic Force Microscopy (AFM),
Magnetic Force Microscopy (MFM), Scanning Tunneling Microscopy (STM),
Near-field Scanning Optical Microscopy (SNOM or NSOM) and others. However,
it can be used for arbitrary height field and image analysis.