Correctly guess deliminter when mixed with commas

Closes #592

papaparse.js

@@ -1245,7 +1245,7 @@ License: MIT
 
 					if (typeof fieldCountPrevRow === 'undefined')
 					{
-						fieldCountPrevRow = fieldCount;
+						fieldCountPrevRow = 0;
 						continue;
 					}
 					else if (fieldCount > 1)
@@ -1258,7 +1258,7 @@ License: MIT
 				if (preview.data.length > 0)
 					avgFieldCount /= (preview.data.length - emptyLinesCount);
 
-				if ((typeof bestDelta === 'undefined' || delta < bestDelta)
+				if ((typeof bestDelta === 'undefined' || delta > bestDelta)
 					&& avgFieldCount > 1.99)
 				{
 					bestDelta = delta;

tests/test-cases.js

@@ -1193,6 +1193,16 @@ var PARSE_TESTS = [
 			errors: []
 		}
 	},
+	{
+		description: "Pipe delimiter is guessed correctly when mixed with comas",
+		notes: "Guessing the delimiter should work even if there are many lines of comments at the start of the file",
+		input: 'one|two,two|three\nfour|five,five|six',
+		config: {},
+		expected: {
+			data: [['one','two,two','three'],['four','five,five','six']],
+			errors: []
+		}
+	},
 	{
 		description: "Single quote as quote character",
 		notes: "Must parse correctly when single quote is specified as a quote character",