Update document about CustomLogLevels

Documentation/CustomLogLevels.md

@@ -18,7 +18,7 @@ You're in luck because **you can customise the log levels however you want**! In
 
 ### Details
 
-The log levels are all defined in `DDLog.h`. All you have to do is create your own header (e.g. `MYLog.h`). Your project files will then import `MYLog.h` instead of `DDLog.h`.
+The log levels are all defined in `DDLog.h`. All you have to do is create your own header (e.g. `MYLog.h`). Your project files will then import `MYLog.h` instead of `CocoaLumberjack.h` or `DDLog.h`.
 
 Within MYLog.h you simply undefine the pre-defined stuff, and then set everything up however you want.
 
@@ -28,6 +28,55 @@ There is a sample Xcode project that comes with Lumberjack that does exactly thi
 Some internal methods, such as `addLogger:`, ignore custom log levels/flags.  
 To avoid unexpected behaviors use more specific methods such as `addLogger:withLevel:`.
 
+MYLog.h:
+```objc
+#import <CocoaLumberjack/CocoaLumberjack.h>
+
+// We want to use the following log levels:
+// 
+// Fatal
+// Error
+// Warn
+// Notice
+// Info
+// Debug
+// 
+// All we have to do is undefine the default values,
+// and then simply define our own however we want.
+
+// First undefine the default stuff we don't want to use.
+
+#undef DDLogError
+#undef DDLogWarn
+#undef DDLogInfo
+#undef DDLogDebug
+#undef DDLogVerbose
+
+// Now define everything how we want it
+
+#define LOG_FLAG_FATAL   (1 << 0)  // 0...000001
+#define LOG_FLAG_ERROR   (1 << 1)  // 0...000010
+#define LOG_FLAG_WARN    (1 << 2)  // 0...000100
+#define LOG_FLAG_NOTICE  (1 << 3)  // 0...001000
+#define LOG_FLAG_INFO    (1 << 4)  // 0...010000
+#define LOG_FLAG_DEBUG   (1 << 5)  // 0...100000
+
+#define LOG_LEVEL_FATAL   (LOG_FLAG_FATAL)                     // 0...000001
+#define LOG_LEVEL_ERROR   (LOG_FLAG_ERROR  | LOG_LEVEL_FATAL ) // 0...000011
+#define LOG_LEVEL_WARN    (LOG_FLAG_WARN   | LOG_LEVEL_ERROR ) // 0...000111
+#define LOG_LEVEL_NOTICE  (LOG_FLAG_NOTICE | LOG_LEVEL_WARN  ) // 0...001111
+#define LOG_LEVEL_INFO    (LOG_FLAG_INFO   | LOG_LEVEL_NOTICE) // 0...011111
+#define LOG_LEVEL_DEBUG   (LOG_FLAG_DEBUG  | LOG_LEVEL_INFO  ) // 0...111111
+
+#define DDLogFatal(frmt, ...)   LOG_MAYBE(NO,  ddLogLevel, LOG_FLAG_FATAL,  0, nil, __PRETTY_FUNCTION__, frmt, ##__VA_ARGS__)
+#define DDLogError(frmt, ...)   LOG_MAYBE(NO,  ddLogLevel, LOG_FLAG_ERROR,  0, nil, __PRETTY_FUNCTION__, frmt, ##__VA_ARGS__)
+#define DDLogWarn(frmt, ...)    LOG_MAYBE(YES, ddLogLevel, LOG_FLAG_WARN,   0, nil, __PRETTY_FUNCTION__, frmt, ##__VA_ARGS__)
+#define DDLogNotice(frmt, ...)  LOG_MAYBE(YES, ddLogLevel, LOG_FLAG_NOTICE, 0, nil, __PRETTY_FUNCTION__, frmt, ##__VA_ARGS__)
+#define DDLogInfo(frmt, ...)    LOG_MAYBE(YES, ddLogLevel, LOG_FLAG_INFO,   0, nil, __PRETTY_FUNCTION__, frmt, ##__VA_ARGS__)
+#define DDLogDebug(frmt, ...)   LOG_MAYBE(YES, ddLogLevel, LOG_FLAG_DEBUG,  0, nil, __PRETTY_FUNCTION__, frmt, ##__VA_ARGS__)
+```
+
+### Legacy Macros(CocoaLumberjack 1.9.x or before)
 MYLog.h:
 ```objc
 #import "DDLog.h"