Consistently prefix warning messages

src/cli/main.cpp

@@ -346,9 +346,9 @@ static void process_file(const fs::path & file, const options & o) {
 			}
 			
 			if(checksum != file.checksum) {
-				log_warning << "checksum mismatch:";
-				log_warning << "actual:   " << checksum;
-				log_warning << "expected: " << file.checksum;
+				log_warning << "checksum mismatch:\n"
+				            << "actual:   " << checksum << '\n'
+				            << "expected: " << file.checksum;
 				if(o.test) {
 					throw new std::runtime_error("integrity test failed");
 				}

src/util/log.cpp

@@ -38,7 +38,7 @@ logger::~logger() {
 		case Debug:   std::cout << color::cyan   << buffer.str() << std::endl; break;
 		case Info:    std::cout << color::white  << buffer.str() << std::endl; break;
 		case Warning: {
-			std::cerr << color::yellow << buffer.str() << std::endl;
+			std::cerr << color::yellow << "warning: " << buffer.str() << std::endl;
 			total_warnings++;
 			break;
 		}

src/util/storedenum.hpp

@@ -77,7 +77,7 @@ public:
 			return Mapping::values[value];
 		}
 		
-		log_warning << "warning: unexpected " << enum_names<enum_type>::name << " value: " << value;
+		log_warning << "unexpected " << enum_names<enum_type>::name << " value: " << value;
 		
 		return Mapping::default_value;
 	}