Update Licensing section

* Add "Installing and Running" section

* Move "Copy to Clipboard" button to header
* Add "FlatHub Page" button to header for visiting the app on FlatHub.

* Fix installing via setup.py
* Add confirmation dialog before (un)installing
* Update message dialog titles
* Make message dialog titles translatable

    * Update a related ref row on the list if a related ref is app
      (not runtime) after uninstalling a related ref.

* Update a related ref row on the list if a related ref is app
  (not runtime) after installing a related ref.

* Fix "Uninstall" menu item function

* Fix "Install" menu item function

* Update some new translatable strings
* Update translations for new translatable strings

        * Make updating cancellable
        * Fix corrupting related row after updating error

    * Make uninstalling cancellable
    * Fix corrupting related row after uninstallation error

* Make installing cancellable
* Fix corrupting related row after installation error

* Update "Versioning" section
* Remove "Roadmap" section, there is no ROADMAP.md
* Fix English on "Licensing" section

Fix an error when uninstalling