Adding Fedora installation into Readme.

Hello, I'm working with Fedora KDE-Sig team and we decided to bring tok under our copr repository building against dev branch so everybody who wants to test/use can install easier and hopefully can give feedback too. Sometimes builds may fail in RPM which is fine. That's why we have copr repository for faster change and fixes. Until it is become stable or released, we will going to publish under copr repository. When it is released, we will also going to add into fedora repository and this repo can be still active against "dev" as a "nightly version" so people can have more options as well.

I put enough information for repo and spec file in description of copr repo1, Plus other distros can add their installation guide and repos into readme too

Thank you.