Lingua-franca

This release contains two hotfixes and a new localization. No breaking changes.

Fixes:
* Bug: In certain languages, `parse.extract_datetime()` returns 08:00 when no datetime is found, instead of returning `None` (Issue 117, PR 118)
* Error: SyntaxWarnings in newer Python releases, caused by misuse of `is` in `lingua_franca.format` (PR 112)

New Localizations:
* `parse.extract_duration()` localized for German/primary lang code `de` (PR 119)

Contributors:
* forslund (`extract_datetime()` fix)
* PureTryOut (`SyntaxWarning` fix)
* emphasize (`extract_duration()` to German)

and a big thanks to ChanceNCounter for facilitating the release!

This release fixes a couple of issues regarding extracting numbers.

- Handle capital letters properly 85
- Fix issue with leading hundreds 86
- Fix even multiples of 10 81
- Make language versions of extract_number use the same signature 77

In addition a couple of other minor fixes:
- Fix pronounce_number for numbers < 1.0
- Fix broken Spanish test 78

Sync with mycroft-core changes.
- Improved Swedish datetime parsing
- Fix handling % characters for English and Portuguese
- Improved Spanish datetime parsing

The first official release of Lingua Franca as a stand alone package.