* Update dutch translation file
* Added a solid solution for removing invoices from "node" overview

19-11-2008:
* Added support for: Invoice number format, 12345, 2008001, 200806001, etc.
  - It's possible now to prefix invoice number with whatever, for example A2008001.

12-11-2008:
* Display invoice comments on the invoice template
* Display pay limit on the invoice template
* Added: Global, per template set which fields to display on the invoice: VAT, Unitcost (ex), Unitcost (inc), Total (ex), Total (inc)
* FIXED BUG: Default template settings seem to don't inherit from general settings
  - Inheriting worked fine, made a small ajustment so it works even smoother now.
  - The main problem was that the preferred locale was not installed on the system. I made that form description more complete now
    and added a list which displays installed locales on the system.
* Added: Translate file for dutch language

11-11-2008:
* FIXED BUG: Functions can never have the same name, also when including just one template (Fatal error: Cannot redeclare _invoice_get_template_output())
* FIXED BUG: Installer is not correct and must be updated (we're using schema files now)
* Added and tested invoice_update_1() function, works 100% correct.

01-11-2008:
* FIXED BUG: Search on a customer starting with "f" or other sprintf() like characters go wrong