Log Message:
Version 2.5.0

New Features
* Numbers: Add currency utilities and helpers
* Support PyInstaller

Minor Improvements and bugfixes
* Dates: Add __str__ to DateTimePattern
* Dates: Fix an invalid string to bytes comparison when parsing TZ files on Py3
* Dates: Formatting zero-padded components of dates is faster
* Documentation: Fix "Good Commits" link in CONTRIBUTING.md
* Documentation: Fix link to Python gettext module
* Messages: Allow both dash and underscore separated locale identifiers in pofiles
* Messages: Extract Python messages in nested gettext calls
* Messages: Fix in-place editing of dir list while iterating
* Messages: Stabilize sort order
* Time zones: Honor the no-inherit marker for metazone names