- fixes german umlauts

GricheldeConstants.lua

@@ -378,6 +378,24 @@ local function getUtf8Table(word)
     return tbl
 end
 
+--- handles UTF-8 characters like äöü (except ß, ÿ, × and ÷)
+local function toUpper(word)
+    return (Grichelde.F.gsub(_G.strupper(word), "\195([\160-\190])", function(c)
+        if (c ~= "\183") then
+            return "\195" .. Grichelde.F.bytes2Char(Grichelde.F.toByte(c) - 32)
+        end
+    end))
+end
+
+--- handles UTF-8 characters like äöü (except ß, ÿ, × and ÷)
+local function toLower(word)
+    return (Grichelde.F.gsub(_G.strlower(word), "\195([\128-\158])", function(c)
+        if (c ~= "\151") then
+            return "\195" .. Grichelde.F.bytes2Char(Grichelde.F.toByte(c) + 32)
+        end
+    end))
+end
+
 local function isLetter(word)
     local char = Grichelde.F.getNextCharUtf8(word)
     return (char ~= nil) and (Grichelde.F.toUpper(char) ~= Grichelde.F.toLower(char))
@@ -514,8 +532,8 @@ Grichelde.F = {
     gmatch          = _G.string.gmatch,
     join            = _G.strjoin,
     split           = _G.strsplit,
-    toUpper         = _G.strupper,
-    toLower         = _G.strlower,
+    toUpper         = toUpper,
+    toLower         = toLower,
     getNextCharUtf8 = getNextCharUtf8,
     isUtf8MultiByte = isUtf8MultiByte,
     getUtf8Sequence = getUtf8Sequence,