custom_rp.pl for csv write of trial balance

[Steve D. <sd...@sw...>]

I've attached a custom_rp.pl that writes the trial balance to a csv
file.  It's for 1.8.x versions since it's in the custom form, but the
changes could be applied to pre 1.8 versions (just edit rp.pl for pre
1.8).

Just stick it in /bin/mozilla and when you check the box it writes the
whole tb for the period entered to a file.  Save the link as
whatever/wherever you want, and open it with a spreadsheet to create
your own reports or do analysis, etc.

I'll eventually do this for the AR, AP, GL, and Inventory reports.

I hope it's useful to everyone.
Steve

manual diff:

lines 114-122 in report function
- new html table row w/ checkbox and link to file

lines 208-246
- new file_trial_balance function

lines 283-294 in generate_trial_balance function
- call new function if box is checked