Resolve "(Re)create DataItems table"
Closes #21 (closed).
Adds three dataitems tables: for raw, external and processed dataitems. The external dataitems are part of the processed dataitems table in the Google docs version. It seemed good to split them because they are not produced by us (or are static calibration files).
The PRO_CATG
and PRO_TYPE
keywords are not yet included, because there is not yet a mechanism to encode this information.
Information from the Google tables have been copied to the data model.