Better design to set the WSF_REQUEST.path_parameters
especially handle the case where the request goes trought more than one route (could be the case when using WSF_ROUTING_HANDLER)
Added WSF_REQUEST.path_parameter (a_name): detachable WSF_VALUE
- fill path_parameters using `import_raw_path_parameters"
when executing the route
- reset to previous value with reset_path_parameters (..),
just in case the request is executed via severals routes.
- removed path_parameter
- added `item' to include WSF_REQUEST.item
- marked obsolete `parameter'
The goal is to remove confusion, remove URI_TEMPLATE specific `path_parameter'
and provide a way to use ctx.item (..) to also include meta variable, query, form, ... items
