[WARNING] Remove unecessary toString calls

The StringBuilder handles the conversion
itself.
diff --git a/core/src/main/java/org/apache/james/mime4j/stream/ParserCursor.java b/core/src/main/java/org/apache/james/mime4j/stream/ParserCursor.java
index edb475e..0a5e2ab 100644
--- a/core/src/main/java/org/apache/james/mime4j/stream/ParserCursor.java
+++ b/core/src/main/java/org/apache/james/mime4j/stream/ParserCursor.java
@@ -79,11 +79,11 @@
     public String toString() {
         StringBuilder buffer = new StringBuilder();
         buffer.append('[');
-        buffer.append(Integer.toString(this.lowerBound));
+        buffer.append(this.lowerBound);
         buffer.append('>');
-        buffer.append(Integer.toString(this.pos));
+        buffer.append(this.pos);
         buffer.append('>');
-        buffer.append(Integer.toString(this.upperBound));
+        buffer.append(this.upperBound);
         buffer.append(']');
         return buffer.toString();
     }