wip - fix PHP strict warning

Fix some warnings on PHP 7.0.25

Warning: Declaration of Users::saveentity($module) should be compatible
with CRMEntity::saveentity($module, $fileid = '') in
/var/www/users/vtiger/content/vtiger.cebe.cc/modules/Users/Users.php on
line 1954

Warning: Declaration of Users::uploadAndSaveFile($id, $module,
$file_details) should be compatible with
CRMEntity::uploadAndSaveFile($id, $module, $file_details,
$attachmentType = 'Attachment') in
/var/www/users/vtiger/content/vtiger.cebe.cc/modules/Users/Users.php on
line 1954

Warning: Declaration of Users::insertIntoEntityTable($table_name,
$module) should be compatible with
CRMEntity::insertIntoEntityTable($table_name, $module, $fileid = '') in
/var/www/users/vtiger/content/vtiger.cebe.cc/modules/Users/Users.php on
line 1954

Warning: Declaration of Users::save($module_name) should be compatible
with CRMEntity::save($module_name, $fileid = '') in
/var/www/users/vtiger/content/vtiger.cebe.cc/modules/Users/Users.php on
line 1954

Warning: Declaration of Users::get_column_value($columname, $fldvalue,
$fieldname, $uitype, $datatype) should be compatible with
CRMEntity::get_column_value($columnname, $fldvalue, $fieldname, $uitype,
$datatype = '') in
/var/www/users/vtiger/content/vtiger.cebe.cc/modules/Users/Users.php on
line 1954