Add (undocumented) attribute metadata_name to <param>
Add (undocumented) attributes to <options>

Add 'options_filter_attribute' attribute
(see lib/galaxy/tools/parameters/basic.py)
Add 'transform_lines' attribute
(see lib/galaxy/tools/parameters/dynamic_options.py)
transform_lines and
Add (undocumented) 'ref_attribute' to <filter>

Add attribute 'ref_attribute' to <filter>
(see lib/galaxy/tools/parameters/dynamic_options.py:153)