Add support for Cordova Globalization API

This commit adds support for feature #686.

All of the mobile-spec tests are now passing and unit tests cover
most of the code.

Most of the settings are via the device panel with some interesting
workarounds:

- no timezone support (just returns ??? for the timezone, we can fix
  this later if someone wants it)
- DayLight savings time is handled via a checkbox in the device
  settings, if checked all dates are returned as isDST
- All number and currency formatting is hardcoded to be North American.
  (can be controlled via the accountingjs if needed)