This patch includes some minor consistency fixes I noticed when reading
the man page:
- A few commands had extra blank lines before starting their description
  which was causing extra whitespace to be added to the description.
- Some information relevant to commands was nested under example
  commands because of leading whitespace (mostly the information about
  `-nevra` commands).
- Some example commands followed their description, while most other
  examples have the command first and then the description. This changes
  all examples to the latter for consistency.
- Renamed the `Examples` header to `Repoquery Examples` similar to other
  example headers
- Fixed typo in repoquery examples (ligttpd -> lighttpd)
- Added parameter names to `swap` description

Also this updates the man page file name in the README (dnf.8 -> dnf4.8)