Feature/language option

[phenze]

Take a look at the following issue for further details:

https://github.com/bk1285/rpi_wordclock/issues/211.

That is always a Problem for me when merging things back in my fork.

Normally you say "dreiviertel 6" and not "viertel vor 6" 👍 . This option is mandatory!

[bk1285]

I see your point, @phenze

However, in most of the cases, stancil_language and language would be the same -- introducing redundant/duplicated information. How about leaving the language as is, introducing an (optional) dialect?

[phenze]

@bk1285 great idea.

I have made the changes. Please check again