Number of mementos does not have place-value delimiter

[machawk1]

See http://machawk1.github.io/wail/images/wail_0.2018.02.09_basic.png,
"5117" should be "5,117" or whatever delimiter is appropriate for the locale (which we currently don't handle, so make it "," initially).

[machawk1]

Re-opening, no longer seems to be working as of 2f264ad

This only appears to be an issue in the .app, not when run from the .py scripts. I wonder if some of the locale settings don't carry over to the binary.

[machawk1]

locale.setlocale(locale.LC_ALL, '') -> locale.setlocale(locale.LC_ALL, 'en_US') will fix this but decouples from the system locale, so will be incorrect (e.g.) in instances where "," and "." are delimiters for decimal and thousands separator, respectively.

[machawk1]

The above breaks the build on Windows, as the en_US locale is not available.