Discontinue file-roller contract, provide archive compression and extraction internally

[jeremypw]

The current dependence on the correct installation of both the FileRoller flatpak and the file-roller contract is fragile. FileRoller is specifically excluded from being shown in the Application Menu so it is essential that Files can be used for this function. Moreover the use of contracts is giving way to portals in the Flatpak world.

We should offer compression and extraction operations internally using e.g. libarchive in a similar way to Nautilus.

[Marukesu]

GVFS already has a archive:// URI that uses libarchive, so we can simply use GLib.Files to extraction and creation support.

But note that FileRoller supports more types of archives than libarchive, so some suport will be lost.

[jeremypw]

Thanks @Marukesu I'll look into that.

[jeremypw]

Presumably the gvfs archive:// backend is intended to make archive files look like a regular folder? So compression and extraction happens transparently on the fly? Neither Dolphin nor Nautilus seem to recognize archive:// URIs at the moment - they launch file roller.