Slightly relaxing tolerances in tidal_channel
Slightly relaxing tolerances in tidal_channel

Commit purely in test XML: following discussion with test owner (Angus), a small relaxation of test tolerance in tidal_channel for Fedora 23.
jrper/fluidity,jjo31/ATHAM-Fluidity,jjo31/ATHAM-Fluidity,jrper/fluidity,iakovos-panourgias/fluidity,iakovos-panourgias/fluidity,jjo31/ATHAM-Fluidity,iakovos-panourgias/fluidity,jjo31/ATHAM-Fluidity,jrper/fluidity,jjo31/ATHAM-Fluidity,iakovos-panourgias/fluidity,jrper/fluidity,jrper/fluidity,iakovos-panourgias/fluidity