Enhancement - strippedLength

- Added a text method that calculates a string length but does not
  include color control codes.

src/text.cpp

@@ -568,3 +568,30 @@ std::string::size_type find (
 }
 
 ////////////////////////////////////////////////////////////////////////////////
+// Return the length, in characters, of the input, subtracting color control
+// codes.
+int strippedLength (const std::string& input)
+{
+  int length = input.length ();
+  bool inside = false;
+  int count = 0;
+  for (int i = 0; i < length; ++i)
+  {
+    if (inside)
+    {
+      if (input[i] == 'm')
+        inside = false;
+    }
+    else
+    {
+      if (input[i] == 033)
+        inside = true;
+      else
+        ++count;
+    }
+  }
+
+  return count;
+}
+
+////////////////////////////////////////////////////////////////////////////////