Generalized met workflow

met.workflow.gen.R can be used for 
- downloading raw NARR
- converting to raw NARR to CF 
- Rechunk/Permuting for faster extraction times
- extracting for specific sites
- met2model.SIPNET (ED2 should also be working)

parameters are set in met.workflow.params.R
Better to change this to be:
SELECT *, ST_X(geometry) AS lon, ST_Y(geometry) AS lat FROM sites WHERE id=
This is a single query and will be faster. Also if you know what columns you need, it is better to specify it explicitly since that will also speed up the query. So if you only need lat/lon from a site, it is better to not have the * in the SQL query.