Changes in trial balance for 1.4

[Chris Travers <..hidden..>]

Hi;

I am now in the process fixing the enhanced_tb add-on for 1.3 and
making it work with 1.4.  Major enhancements include:

1)  Trial balances can now roll forward from checkpoints, provided
that yearends are not ignored.  This means that if you have a larger
db, the trial balance will not keep getting slower as you add data.
2)  One can run a trial balance on a subset of accounts (note these
are not expected to balance but are sometimes used for things like
cash control)
3)  One can save trial balances and run them later with the same parameters.

Best Wishes,
Chris Travers