src: Fixing signed/unsigned comparison warnings and removing all warning-suppressing pragmas

Change-Id: I5526a00d9be6d576bb500d51c0bc6c2ad8cc541d
diff --git a/src/key-locator.hpp b/src/key-locator.hpp
index 2ff85f0..a3fb896 100644
--- a/src/key-locator.hpp
+++ b/src/key-locator.hpp
@@ -18,7 +18,7 @@
   struct Error : public std::runtime_error { Error(const std::string &what) : std::runtime_error(what) {} };
   
   enum {
-    KeyLocator_None = -1,
+    KeyLocator_None = 4294967295,
     KeyLocator_Name = 0,
     
     KeyLocator_Unknown = 255