Update test cast for issue 4.

There may be *more* attributes in the axes after saving to netcdf and reloading,
since standard_name is no longer scraped out of the atts in cfmeta.
Attempt to correct portability issue with timeaxiscore module; also improved its error reporting.
Added ModelTime360 to default imports from timeaxis
Removed scaling from axis formatter (may break plot_v1 behaviour?!)
Fixed issue with concatenating along dummy axis
'sorted' flag now influences file list ordering; default changed to True
Added a default plottitle to Spectral axis
regress now takes a comma-separated string to specify outputs, like EOF
Can now specify a format string to formatter()
Numerous plotting fixes and upgrades, including support for quiver plots, some improved defaults, better axis and variable titling logic, better text transform options
Added a few details to the new plotting package support