Version 3.1.0

• Added support for mtype=None to variogram_fit.
• Added support for res="None" to create_map.
• Added errfunc support to kriging.
• Added cfgfilter to cfgmanager.
• Added proj param to basemap.get_proj.
• Added closing after showing in core_plot.
• Added autoscaling mode to ScalarMappable.get_levels with normal and degrees.
• Added merge_masks to merge masks of several variables.
• Added u, v, ubc, vb, speed, cdir, sigma*, *dens and renamed vol to cvol in cf.
• Added support for redirecting warnings, stdout and sterr to io.Logger
• Added mode support to dz2depth with edge, edge+ and middle.
• Added checkdir to make sure dir exists.
• Added julday converter.
• Added support for haversine distance to get_distances + krig integration.
• Added cyclic support to rainbow.
• Changed grid2xy to use get_distances.
• Renamed dmax to distmax in kriging.
• Improved support of julian days in atime.
• Improved date locators and formatters.
• Fixed cmap_br*.
• Fixed ignorecase in ncmatch_obj.
• Fixed some proj problems in misc.grid.
• Fixed inversions in kriging.
• Fixed validation of list in config.
• Fixed 360 deg problem for grid2xy.
• Fixed transect with 4D data
• Fixed scalar handling and masking in grid2xy
• Fixed format_var with variables with no axes specs.
• Fixed roundto in IterDates.
• Fixed no_norm issue.
• Fixed some standard names and grid locs in cf.