Trigfind module returns error, could be reduced to warning

[jrsmith02]

ValueError: No channel-level directory found at /home/detchar/triggers/H1/GDS_CALIB_STRAIN_OMICRON. Either the channel name or ETG names are wrong, or this channel is not configured for this ETG.

The trigfind module will return an error whenever the channel directory for Omicron is not found. The above error could be reduced to a warning so that hveto can continue past this.