Minor fixes for recent CLang.

Needed for CLang 3.2.

include/cln/exception.h

@@ -3,6 +3,7 @@
 #ifndef _CL_EXCEPTION_H
 #define _CL_EXCEPTION_H
 
+#include <string>
 #include <stdexcept>
 
 namespace cln {

tests/test_I_io.cc

@@ -7,7 +7,7 @@ int test_I_io (int iterations)
 	int error = 0;
 	for (int i = iterations; i > 0; i--) {
 		cl_I a = testrandom_I();
-		int base = iterations % (36-1) + 2;
+		unsigned base = iterations % (36-1) + 2;
 		cl_read_flags rflags = {syntax_integer, lsyntax_standard, base};
 		stringstream buf;
 		print_integer(buf, base, a);