Remove 'using namespace std' from SerialTypes.h

This unfortunately cuases a ton of flow-down changes because a lot of other
code was depending on that definition existing. This has a fairly large chance
to break builds of external plugins, considering how many internal ones it broke.

src/logging/writers/sqlite/SQLite.cc

@@ -11,6 +11,7 @@
 #include "SQLite.h"
 #include "sqlite.bif.h"
 
+using namespace std;
 using namespace logging;
 using namespace writer;
 using threading::Value;