support refinement of POSITION in EDPluginGroupXDS
Created by: JieNanMAXIV
The fix is for the error msg (see below) when having POSITION in refinement, i.e. REFINE(INTEGRATE)= POSITION in XDS.INP. File "/mxn/groups/biomax/cmxsoft/edna-mx_new/mxPluginExec/plugins/EDPluginGroupXDS-v1.0/plugins/xdscfgformat.py", line 60, in call raise ValueError("val %s not in %s" % (val, self.possible_values)) ValueError: val POSITION not in ['ALL', 'DISTANCE', 'BEAM', 'AXIS', 'ORIENTATION', 'CELL']