The recommended way to install tweeper globally is to install all its files
under /usr/share/php/tweeper and then make a symlink to the wrapper script
"tweeper" under /usr/bin
+
+NOTES FOR PACKAGERS
+
+Even though the php json extensions are used, namely json_decode(), a direct
+dependency on php-json is not usually strictly necessary, because (at least on
+Debian) php-cli already depends on it.
+
+Tweeper depends on php-symfony-serializer which is used to convert json to xml
+for some sites which provide the timeline data in json rather than in directly
+transformable html.
+
+Tweeper also depends (indirectly) on php-symfony-property-access because the
+code relies on the ObjectNormalizer class which requires the PropertyAccess
+component, see
+http://symfony.com/doc/current/components/serializer.html#installation