Some locales don't have a gregorian calendar, which was causing thor export issues.
Merge pull request #14 from camertron/fix_thor_export

Thor export problems
Upgrading to CLDR 23, fixing day format variants so they don't override the defaults
Fixing calendar 'fields' export to comply with CLDR 23 format
Merge branch 'master' into day_period_variants
Character order (RTL vs LTR) info changed in CLDR 23, updating