Adjust currency box to perform correctly in displaying decimal places.
Fixes to Gift screens to handle empty currency boxes
Fixes to currency textbox and changes to gift forms
Knock on changes after fixing op:2043
Knock on changes after fixing currency textbox and subsequent testing.
Ready for trunk
merge from Branch '~chris-thomas/openpetraorg/dev_20130909_Finance_CurrencyTextBox'.
merge from lp:openpetraorg