rename sys functions to runtime,
because they are in package runtime.

another step to enforcing package boundaries.

R=r
DELTA=732  (114 added, 93 deleted, 525 changed)
OCL=35811
CL=35824
diff --git a/test/runtime.go b/test/runtime.go
new file mode 100644
index 0000000..5bf76e0
--- /dev/null
+++ b/test/runtime.go
@@ -0,0 +1,20 @@
+// errchk $G $D/$F.go
+
+// Copyright 2009 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// make sure that even if a file imports runtime,
+// it cannot get at the low-level runtime definitions
+// known to the compiler.  for normal packages
+// the compiler doesn't even record the lower case
+// functions in its symbol table, but some functions
+// in runtime are hard-coded into the compiler.
+
+package main
+
+import "runtime"
+
+func main() {
+	runtime.printbool(true);	// ERROR "cannot refer"
+}