Add regular expression based localization to PeriodFormatterBuilder and
PeriodFormat. Add Polish locale to PeriodFormat. Add tests.
Remove vicious tabs. Fix order of the supported languages in
PeriodFormat#wordBased(Locale) method's javadoc.
Assure immutability of RegExAffix. Fix formatting.
Merge branch 'gswierczynski-master'
Add regex based period formats

Fixes #166
Bump version to snapshot