remove wrong toFloat function

Amounts should never be converted to floats, the one use of the function was bogus.

src/amounts.ts

@@ -264,14 +264,6 @@ export function parseOrThrow(s: string): AmountJson {
 }
 
 
-/**
- * Convert the amount to a float.
- */
-export function toFloat(a: AmountJson): number {
-  return a.value + (a.fraction / fractionalBase);
-}
-
-
 /**
  * Convert a float to a Taler amount.
  * Loss of precision possible.

src/webex/pages/return-coins.tsx

@@ -70,7 +70,7 @@ class ReturnSelectionItem extends React.Component<ReturnSelectionItemProps, Retu
     });
     this.state = {
       currency: props.balance.byExchange[props.exchangeUrl].available.currency,
-      selectedValue: Amounts.toFloat(props.balance.byExchange[props.exchangeUrl].available).toString(),
+      selectedValue: Amounts.toString(props.balance.byExchange[props.exchangeUrl].available),
       selectedWire: "",
       supportedWires,
     };