Create xs: a void source Fork object to provide a fluid interface with a ...
namespace for other Forks:

  Example:
    Publish a sales dataset from a 'sales' file:

    xs.file( 'sales' ).publish();

    The xs objects acts a namespace for XS chainable pipelets. Without the xs
    object, one would have to write the following less fluid code where the
    xs namespace is not explicit and requiring the new operator on a class to
    create the fist pipelet of a chain:

    new File( 'sales' ).publish();

 Also:
   - XS.prototype.set() now provides a parameter to provide an Array of objects for
     initialization. This allows to write xs.set( [...] ) instead of requiring the less
     fluid new Set( [...] )
   - Modify tests to use the new form xs.set( [...] ) instead of new Set( [...] )