Updates for tx1m

[apcraig]

This does several things for tx1m,

• Updates the test lists, adds tx1m tests
• Proposes minor updates to the documentation
• Adds new decomps for tx1m. This is useful for being able to test bit-for-bit with different block counts and for running on greater varieties of pe counts without running out of blocks.

and a few things discovered during tx1m testing,

• Fixes some issues in the sumchk unit tester to cover land block elimination better
• Adds nblock_max (max blocks on a pe across all pes) and nblocks_active (total active blocks) as static module data. These are useful scalars to store in general. We had been just computing them and printing them out but not storing them.

[anton-seaice]

I think youll need to move the ,& inside the #ifdef, otherwise this won't compiled unless USE_NETCDF is true

[apcraig]

Good catch, I confirmed it's a problem and just pushed a fix.

[anton-seaice]

For future reader, this is related to CICE-Consortium#1132

[anton-seaice]

Thanks @apcraig