Establish modifications to QC process

[benjwadams]

Please list desired changes to QC process. This does not directly include things like the documentation and migrating to the ioos_qc library.

So far:

1. Always apply QARTOD to variables, regardless of whether user supplied QC variables are provided.
2. Eliminate _qc variables which appear unused in favor of aggregate flags.

[leilabbb]

• Need to create an event driven workflow to set a priory for real time data files to be QCed first.
• Need to use all files in a deployment to consolidate a comprehensive list of variables to be QCed.
• Need to warn against variables with invalid standard names or dimensions that prevent QARTOD variables creation.
• Need to ensure that the created QARTOD variables are available to end users on ERDDAP.

[kerfoot]

One additional change:

1. Remove the 15 or so legacy variables noted in issue #268 unless they are included in the files submitted by the data providers.

[benjwadams]

1. in original post should be split out into separate issue if it isn't already.

2. Implement aggregate QC flags to meet NDBC GTS Ingest requirements #277 covers aggregate flags,
   Removal of all unused legacy _qc variables #278 covers legacy *_qc variables.

Would recommend closing this issue once adequately split up.

[kerfoot]

I would suggest closing this as I believe it is being addressed in a series of other issues that are more specific with the overall goal of establishing an updated QC process.

[kerfoot]

All issues/comments above have been addressed in smaller, more focused issues. Closing.