Statistics now work on scalar values (0d arrays)

support GUI Display Data on 0d variables

For variables who shape is "0" (that is, a simple scalar value), statistics calculations now work.  Although many of the statistics are silly, this is useful for report generation.

Implementation: DataObject has a new function "holding_array" which in most cases returns itself. But if self.data.shape==0, it returns a copy of itself with self.data's scalar value tossed into a single element array.  Now that the data is an array, as expected, the statistics code works fine.

"Data shape" shows single value arrays directly

Typo fix (Historgram->Histogram)

add --parsable, formatting info output for parsing

if glance info can't read files, return non-zero

Sort variables in output from stats & inspectStats.

"glance info --parsable" now outputs the results in tab deliminated format, repeating the filename on each line, making it easier to parse programmatically. Additional fields may be added later!

At the moment only supports "info".  May add support for other formats later.

In glance gui, if a variable has only a single value, it will be displayed directly in the "Data shape" field.

A 0 dimention numpy array is weird.  It's neither a scalar, nor a 1 dimensional array with a single element. "Display Data" silently refused to work for such values.

This change converts the 0d array into a 1d array with a single element immediately before trying to display it.  Result: Display Data now works on 0d arrays, showing the single value as expected.

Put sort directly into for loop; don't bother with giving it a variable.
Use named argument instead of relying on positional one.

Returns how many files could not be read, to a maximum of 255 (since the exit code is 8 bit).
This allows other processes calling "glance info" to detect errors.

glance --version now returns 0

Gui load files

Previously output was ordered in whatever order the set happened to offer them in. This was not stable between different Python versions.  Ordered alphabetically(ish) should be more human friendly, and will simplify the tests.

Previously "glance --version" was treated as an error, and the process's exit code was "9".  Displaying the version isn't an error.

If present, the first one or two arguments to "glance gui" will be automatically loaded as File A and File B.

"glance help FOO" is now case insensitive

Command names are case insensitive.  "glance reportGen" and "glance reportgen" are synonymous.

However, help requests remain case sensitive. "glance help reportgen" fails.  This patch makes it case insensitive.

"python -m glance.compare"→"glance" in documentation

Typo fix: remove extra space.

Typical usage has changed; not usually just invoked through the "glance" binary. Change documentation to match.

fix handling of _unsigned attribute in nc files; units=1 no longer display on plots; commands on the command line should be case sensitive; better handling of shape () data

adding a new density scatter plot and putting limits on how much data glance will be willing to plot in traditional scatter plots and hex plots