exist documentation errors

[KitWallace]

In reviewing the wikibook, errors in the documentation are found . This is a log of them

[KitWallace]

system:export
text is wrong : Restore the database or a section of the database (admin user only). r/Restore/Export/

similarly for system:export-silently

[KitWallace]

xmldb:permissions-to-string

Returns:
xs:string? : the permissions as string 'rwu' for, user, group and other

the permission characters are rw and x

similarly
xmldb:string-to-permissions

has .."The permissions string should be in the format 'rwxrwxrwx' where r is read, w is write and u is update.