pakfire: Refactor dblist seperating UI and logic

pakfire: Refactor dblist seperating UI and logic

- Removed UI code from dblist function and refactor it making it return
  a hash representing the pak db for easier handling of this data.
- Moved core update check in dblist to new seperate dbcoreinfo function
  making it return a hash with current and possibly available core
  version info.
- Update existing calls to dblist
- Bring UI parts previously in dblist to pakfire program itself,
  pakfire.cgi and index.cgi with a few small enhancements:
  - Translations for 'Core-Update', 'Release', 'Update' and 'Version'
  - Add currently installed version numbers to installed paks list in
    pakfire.cgi
  - Add 'Installed: yes/no' to pakfire list output so people not using
    colors have this information too. (Partly fixes Bug #12868)
  - Add update available details to pakfire list output if package has
    updates available.

Signed-off-by: Robin Roevens <robin.roevens@disroot.org>