add missing header end comments

- ensures a consistent usage in header files
- also add a blank line after the copyright header where missing
- also remove orphan new-lines at the end of some files

src/keystore.h

@@ -105,4 +105,4 @@ public:
 typedef std::vector<unsigned char, secure_allocator<unsigned char> > CKeyingMaterial;
 typedef std::map<CKeyID, std::pair<CPubKey, std::vector<unsigned char> > > CryptedKeyMap;
 
-#endif
+#endif // BITCOIN_KEYSTORE_H