replaced stream-based number formatting

embedded a portion of double-conversion library
(http://code.google.com/p/double-conversion/)and replaced stream-based
number formatting

Foundation/testsuite/src/StringTest.h

@@ -71,6 +71,8 @@ public:
 	void benchmarkStrToInt();
 
 	void testIntToString();
+	void testFloatToString();
+	void benchmarkFloatToStr();
 
 	void setUp();
 	void tearDown();
@@ -132,7 +134,6 @@ private:
 		istr >> value;
 		return istr.eof() && !istr.fail();
 	}
-
 };