rename APInt::toString -> toStringUnsigned for symmetry with toStringSigned()

Add an APSInt::toString() method.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41309 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/examples/Fibonacci/fibonacci.cpp b/examples/Fibonacci/fibonacci.cpp
index cd35417..d0ffb9a 100644
--- a/examples/Fibonacci/fibonacci.cpp
+++ b/examples/Fibonacci/fibonacci.cpp
@@ -116,6 +116,6 @@
   GenericValue GV = EE->runFunction(FibF, Args);
 
   // import result of execution
-  std::cout << "Result: " << GV.IntVal.toString(10) << "\n";
+  std::cout << "Result: " << GV.IntVal.toStringUnsigned(10) << "\n";
   return 0;
 }