Contrib: Non profit reports: generate only CSV files, better sorting, more flexible hyperlinks & pagebreaks

This is a series of commits to the non-profit audit reports contrib/ area that I've been working on.

These commits change the output for all reports to just be CSV files, and sort the accounts in a way preferred by our auditors (and presumably other accountants as well).

Also included are improvements to csv2ods.py to improve the generation of hyperlinks and pagebreaks.