Fix codestyle
Refactor CurrencyService

Ask for ExchangeRate instead of DateTime
Fix LoanService::applyForLoan

From now on we have to explicitly use the exchange rate instead of
relying on the date
Rename pending activation to borrower activation
Add Borrower review
Update FeedbackMessage schema
Add ZidishaValidator
Add activation status constants/methods to Borrower
Add BorrowerMailer::sendLoanFeedback
Update feedback messages on the borrower's dashboard
Add activation feedback
Add Borrower::isVerified
Small fix borrower dashboard
Update borrower activation index
Add borrower verification