Avoid ReDOS on float dynamic typing (#779)

Fixes #777

papaparse.js

@@ -1006,7 +1006,7 @@ License: MIT
 		// One goal is to minimize the use of regular expressions...
 		var MAX_FLOAT = Math.pow(2, 53);
 		var MIN_FLOAT = -MAX_FLOAT;
-		var FLOAT = /^\s*-?(\d*\.?\d+|\d+\.?\d*)(e[-+]?\d+)?\s*$/i;
+		var FLOAT = /^\s*-?(\d+\.?|\.\d+|\d+\.\d+)(e[-+]?\d+)?\s*$/;
 		var ISO_DATE = /(\d{4}-[01]\d-[0-3]\dT[0-2]\d:[0-5]\d:[0-5]\d\.\d+([+-][0-2]\d:[0-5]\d|Z))|(\d{4}-[01]\d-[0-3]\dT[0-2]\d:[0-5]\d:[0-5]\d([+-][0-2]\d:[0-5]\d|Z))|(\d{4}-[01]\d-[0-3]\dT[0-2]\d:[0-5]\d([+-][0-2]\d:[0-5]\d|Z))/;
 		var self = this;
 		var _stepCounter = 0;	// Number of times step was called (number of rows parsed)