Bug 9238 - make fund pull down say 'select fund', not 'select budget'

Bug 9238 - make fund pull down say 'select fund', not 'select budget'

When adding a new order to a basket the fund selection field is labeled
"Fund:" but the default option is "Select a budget." This patch changes
this string to "Select a fund" and also corrects the associated
JavaScript error message text displayed when one doesn't choose a fund.

To test, add an order to basket. The "New order" form should show
"Select a fund" as the default option for "Fund" in the "Accounting
details" section. If you submit the form without selecting a fund the
error message should read "You must select a fund."

Signed-off-by: Nicole C. Engard <nengard@bywatersolutions.com>
tests pass

Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
String updates only, passes koha-qa.pl

Signed-off-by: Galen Charlton <gmc@esilibrary.com>