Improve the app description in Fastlane

[yurtpage]

The app description in F-Droid looks not ideal https://f-droid.org/ru/packages/io.github.subhamtyagi.ocr/index.html

Formatting is markdown based but the Fastlane allows only some basic HTML tags. For a regular users it's too many details (like Licenses). Some phrases causes errors on translation.

So here I reworked the text and added one translation for a testing. The diff looks big but in fact there are just a lot of minor changes.

[yurtpage]

Please review the PR