explorer tar.gz (and other compressed files) 7z.dll

Hi,

an bit improvement with 7zip
and the 7z.dll to use on tar.gz
https://sourceforge.net/p/sevenzip/discussion/45798/thread/7dc02e34/
with this dll could Reactos support all really need compressed packs.
it could exist an download routine for download an extract the dll into
the system, automatically if an checkbox selected (use 7z.dll) to stay
on GPL2 compatibility but give the possibility for using 7z.dll

best regards
Blacky