[facet] create a RangeRQLPathFacet (closes #2852512)
This facet is a mix between a RQLPathFacet and a RangeFacet, allowing
to use the FacetRangeWidget on the RQLPathFacet target attribute
import ConfigParser
try:
undo_actions = config.cfgfile_parser.get('MAIN', 'undo-support', False)
except ConfigParser.NoOptionError:
pass # this conf. file was probably already migrated
else:
config.global_set_option('undo-enabled', bool(undo_actions))