[REF] Fix typing in comments

Comments should start in uppercase.
[REF] Call tar system save

Using '-' on the tar options is optional, but on some systems this may
fail.
Add '-' to the tar options to be more robust.
[REF] Add type hint annotations
[REF] Clear composer.json
[ENH] Implementation of base restore command

Implementation of sql restore using system gunzip piping to mysql.

Implementation of assets restore using system tar.