Pygeode

- Fixed some padding logic in showgrid.
- Corrected bug that was happening when the inx coordinate variable was
provided with more than one axis but not as many axes as the data.
- Disable prefix checks when there's an exact match to an axis name.
Fixes bug triggered by axis names that contain underscores.

- Allow some settings to be read from a configuration file (pygrc).
- Added an option to disable lazy array evaluation, for cases where this
feature gets in the way.
- Option to back variables into "shorts" when saving netCDF files,
triggered by passing pack=True to netcdf.save().
- Allow specifying an "unlimited" dimension when saving netCDF files.
- Added load() method to Dataset objects, to load all the associated
variables in memory.
- New plot routines: vstreamplot, vhist, and fill_between.
- New plot.cm module to help with colormaps.
- New plot.cnt_helpers module for setting up contour intervals.
- New "yearlymean" and "climstdev" operators in climat module.
- Allow weights to be used in variance operator.
- Added second-derivative operator (triggered by passing df=2 to "deriv").
- New forward difference operator ("diff").
- Added conjugation operator ("conj").
- Added option to compute covariance matrix of regression coefficients in
multiple_regress.
- New "s_" prefix for axis subsetting, to "squeeze" the axis out after
selecting a particular value.
- New "n_" prefix for axis subsetting, to "negate" the selection criteria.
- New "station" axis, for data that's sample at predetermined surface stations.
- Also, added more general "non-coordinate" axes where the values are not
part of a continuum, and need not even be numeric.
- New time axis constructor helpers (standardtimerange, standardtimen,
modeltime365range, modeltime365n, modeltime360range, modeltime360n,
yearlessn).
- New "check_multi" routine in formats.multifile, to pre-scan all files and
report any problems with the files.
- New "formats.data_scanner" module for loading more general (heterogeneous)
files together into a dataset.
- Added some new and interesting bugs to the code.

- Fixed missing parentheses in interp.c, which could cause a compilation failure.
- Fixed RPM installation configuration.
- Switched from distutils to setuptools, in order to make wheel files.

- Fixed segmentation fault when initializing a time axis with an invalid month.
(issue 76).
- Allow tools.loopover to handle Axis arguments. Certain operations such as
smooth() were crashing when operating on an Axis object (issue 86).
- Preserve variable metadata when doing climatologies (issue 89).
- In multifile.openall(), don't require a format if an opener is provided.
(issue 90).
- Fixed a pointer issue in interpcore, in the case where there aren't enough
valid points to do an interpolation.

- Set attribute Conventions="CF-1.0" in netcdf output files, so other netcdf
utilities know how to parse our data.
- Added system include paths for non-standard prefix installs (conda), as well
as to the libhelper routines for finding libraries

- Allow other PyGeode formats to be installed in parallel Python paths.
- Add LD_LIBRARY_PATH to search path in libhelper.find_library().
- Force double-precision in val_as_date, to prevent precision loss when
computing dates.