Update VBA-JSON to v1.0.3

Author: timhall

src/WebHelpers.bas

@@ -1763,7 +1763,7 @@ Private Function web_GetUrlEncodedKeyValue(Key As Variant, Value As Variant) As
 End Function
 
 ''
-' VBA-JSON v1.0.2
+' VBA-JSON v1.0.3
 ' (c) Tim Hall - https://github.com/VBA-tools/VBA-JSON
 '
 ' JSON Converter for VBA
@@ -2190,6 +2190,13 @@ Private Function json_Encode(ByVal json_Text As Variant) As String
     For json_Index = 1 To VBA.Len(json_Text)
         json_Char = VBA.Mid$(json_Text, json_Index, 1)
         json_AscCode = VBA.AscW(json_Char)
+
+        ' When AscW returns a negative number, it returns the twos complement form of that number.
+        ' To convert the twos complement notation into normal binary notation, add 0xFFF to the return result.
+        ' https://support.microsoft.com/en-us/kb/272138
+        If json_AscCode < 0 Then
+            json_AscCode = json_AscCode + 65536
+        End If
 
         Select Case json_AscCode
         ' " -> 34 -> \"