Add Belarusan layout

[Belarusan]

Checklist

• I made sure that there are no existing issues - open or closed - to which I could contribute my information.
• I made sure that there are no existing discussions - open or closed - to which I could contribute my information.
• I have read the FAQs inside the app (Menu -> About -> FAQs) and my problem isn't listed.
• I have taken the time to fill in all the required details. I understand that the bug report will be dismissed otherwise.
• This issue contains only one feature request.
• I have read and understood the contribution guidelines.
• I optionally donated to support the Fossify mission.

Feature description

Please add the Belarusan (Belarusian) layout. I don't really understand how to use GitHub or create a layout myself, but I'm willing to do it if someone helps me and explains the process.

Why do you want this feature?

I have tried many keyboards, but either there was no Belarusan layout, or it was imperfect. As an active user of the Belarusan language (native), it is very important for me that the layout is convenient and includes important additional symbols.

I'm not the only one who longs for a keyboard with a convenient layout. If one becomes available, I will be able to recommend Fossify Keyboard to others.

Additional information

I am a professional Belarusan translator, so I believe I can create a good layout that meets the needs of the community.

[Belarusan]

I figured it out and created a Pull Request, I hope everything is correct. So far only the Cyrillic version.

upd: Added the Latin version as well.