[cli_install] add option to exclude snmp imports

This process takes a very long time and is not mandatory for an upgrade.
fix missing manifests files from 0.84+1.0 upgrade

This fix needs to restore the `glpi_plugin_fusinvdeploy_fileparts` and
`glpi_plugin_fusinvdeploy_files` tables from some 0.83 backup in order
to restore the manifest files.

fixes #2446
replace use of POST arguments by method parameter

This was not broken until i make use of this method in update.php .
json order fixer code

This will make sure the JSON orders in database are valid and fix it
otherwise.

fixes #2445