Update batches script to include release ID from the command-line

[agstephens]

This is the script to work out a sensible number of batches to run on LOTUS for restructuring the land observations:

https://github.com/glamod/glamod-ingest/blob/master/scripts/land/decide-land-batches.py

At the moment it has release 2 ("r2.0") hard-coded in it.

@jhaigh0 : Please refactor so that "r2.0" is sent in via the command-line and all the relevant variables that use it are modified and are accessible in the right places within the code.

[agstephens]

You could follow this approach for including the release parameter:

https://github.com/glamod/glamod-ingest/blob/master/scripts/land/restructure-land.py

[agstephens]

Once done, you'll need to start adding "r3.0" entries into this file:

https://github.com/glamod/glamod-ingest/blob/master/lib/glamod/settings.py