Fix account_partner_balance report

[ADD] Add in .gitignore file .settings file from eclipse
[FIX] Fix account_partner_balance_report. Fix compute_exchange_rate
method in odt and py file
[FIX] Fix template odt in compute_exchange_rate function
Fix template odt in xml record on base64 codification

[FIX] Fix template odt in xml record on base64 codification