[rpm/meecast.spec] Fix writing dconf key, license etc. (#52)

* [rpm/meecast.spec] Fix writing dconf key, license etc.

Addresses issue #50

* [rpm/meecast.spec] Count up release number …

… for all packages whose the spec file entries were altered.

* [rpm/meecast.spec] Delete spectacle's comments, rectify changelog format, …

… add missed `exit 0` to a scriptlet to make it fail-safe, omit superfluous `-n %{name}-%{version}` for `%setup -q` and omit  long superfluous `rm -rf %{buildroot}` in `%install` section.

* [rpm/meecast.spec] Fix two typos in `%changelog`

* [rpm/meecast.spec] Fix `%sailfishos_version` format error