Do not apply filters on empty values with skip="empty"

This should close https://github.com/racke/Template-Flute/issues/73
Add currency options to skip empty test in order to pass with en_US locale.
Skip new tests for skip feature in case Number::Format isn't available.
Merge branch 'melmothx-topic/gh-73'
Bump up version number.
Prepare Changes and README files for upcoming release.
Add test to reproduce bug caused by multiple lists using same iterator (GH #75).