Update PacFIN landings section

[iantaylor-NOAA]

Self-assigned by @kellijohnson-NOAA in the Google Doc

[iantaylor-NOAA]

Jim says that the text about trawl vs non-trawl landings being broken down by month and INPFC area is not accurate.
We mostly divide catch by state or the 40-10 boundary and not INPFC boundaries in recent years anyway. Perhaps the status-quo language came from the old summary tool that Pacific States hosted, but no longer an issue the way people get data now.

[okenk]

I was using LANDED_WEIGHT_MTONS and was told to use ROUND_WEIGHT_MTONS. This was not obvious to me.

[chantelwetzel-noaa]

Agreed. I think we delete the following sentences:

"Note that the PacFIN catch can be broken down by INPFC or month only for the trawl component, not the non-trawl gears. Also, beware double counting based on multiple levels of aggregation.

PSMFC areas do not contain all of the catch, thus it is best to use INPFC areas to aggregate catch."

I agree that with @okenk comment above that it would be more useful in this section to include information about the columns we should be using and the columns that allow you to identify tribal and research landings.