Review and Publish currency conversion to EUR

[dave-mills]

All project budgets should be available in:

• The project's own currency (for project-level review)
• The organisation's default currency; (for org-level review)
• Euros - for site-wide / global review.

This feature has been developed and needs a review on the staging site. We should do the following:

• [ ] Review / confirm the feature is working on staging (Dave)
• [ ] Deploy it to live. (Dan)