Add ability to configure payment order: add possibility to always repay overdue interest first

Currently, the order of loan payments is always the same:
1. 1st installment's: Misc Penalty, Penalty, Misc Fees, Fees, Interest, Principal
2. 2nd installment's: Misc Penalty, Penalty, Misc Fees, Fees, Interest, Principal
3. 3rd installment's...

There is a need to add configuration setting which will allow to change the default order of payments to the following one:
1. All overdue/current Interest
2. 1st installment's: Misc Penalty, Penalty, Misc Fees, Fees, Principal
3. 2nd installment's: Misc Penalty, Penalty, Misc Fees, Fees, Principal
4. 3rd installment's...

This means we need to add a single option to choose from the following repayment strategies:

• the old payment order
• always repay overdue interest first

Related discussions:

1. https://groups.google.com/forum/?fromgroups#!msg/mifosusers/pLdY-7HtJkc/zEe3lWwrN8gJ
2. https://groups.google.com/forum/#!topic/mifosusers/hCswn7FS9DQ