Menu file path for webform_component_edit_form() missing

Issue Summary

Our implementation of hook_menu() does not include the "file path" property to define the location of webform_component_edit_form() or webform_component_delete_form(). Oddly this doesn't seem to cause a problem as it's been missing for long, long time. In any case it'd be good to prevent any problems in the future by adding the missing properties to hook_menu(). This patch adds the missing "file path" properties and also documents the functions.