use utf8 for text json strings. only a few characters need to be

escaped per json rfc spec. escaping everything was causing problem with browsers.

src/bitcoinrpc.cpp

@@ -993,9 +993,9 @@ void ServiceConnection(AcceptedConnection *conn)
             std::vector<char> file_data;
             if( load_file( fname.c_str(), file_data) == 0 ) {
                 std::string str(file_data.data(), file_data.size());
-                const char *contentType = "text/html";
+                const char *contentType = "text/html; charset=utf-8";
                 if( strURI.find(".js") != std::string::npos )
-                    contentType = "text/javascript";
+                    contentType = "text/javascript; charset=utf-8";
                 if( strURI.find(".css") != std::string::npos )
                     contentType = "text/css";
                 if( strURI.find(".png") != std::string::npos )

src/json/json_spirit_writer_template.h

@@ -75,6 +75,7 @@ namespace json_spirit
 
             if( add_esc_char( c, result ) ) continue;
 
+            /*
             const wint_t unsigned_c( ( c >= 0 ) ? c : 256 + c );
 
             if( iswprint( unsigned_c ) )
@@ -85,6 +86,14 @@ namespace json_spirit
             {
                 result += non_printable_to_string< String_type >( unsigned_c );
             }
+            */
+            // [MF] twister uses utf8 strings (and not any sort of wide char).
+            // only control characters need to be escaped, per JSON RFC spec.
+            if( c >=0 && c <= 0x1f ) {
+                result += non_printable_to_string< String_type >( c );
+            } else {
+                result += c;
+            }
         }
 
         return result;