Update README

- Closes apsdehal#11

README.md

@@ -1,15 +1,57 @@
+
 # go-logger
 
 [![Build Status](https://travis-ci.org/apsdehal/go-logger.svg?branch=master)](https://travis-ci.org/apsdehal/go-logger)
 [![GoDoc](https://godoc.org/github.com/apsdehal/go-logger?status.svg)](http://godoc.org/github.com/apsdehal/go-logger)
 
 A simple go logger for easy logging and debugging of your programs
 
+# Preview
+[![Example Output](examples/example.png)](examples/example.go)
+
+# Formatting
+By default all log messages have format that you can see above (on pic).
+But you can override the default format and set format that you want.
+
+You can do it for Logger instance (after creating logger) ...
+```go
+log, _ := logger.New("pkgname", 1)
+log.SetFormat(format)
+```
+... or for package
+```go
+logger.SetDefaultFormat(format)
+```
+If you do it for package, all existing loggers will print log messages with format that these used already.
+But all newest loggers (which will be created after changing format for package) will use your specified format.
+
+But anyway after this, you can still set format of message for specific Logger instance.
+
+Format of log message must contains verbs that represent some info about current log entry.
+Ofc, format can contain not only verbs but also something else (for example text, digits, symbols, etc)
+
+### Format verbs:
+You can use the following verbs:
+```
+%{id}           - means number of current log message
+%{module}       - means module name (that you passed to func New())
+%{time}			- means current time in format "2006-01-02 15:04:05"
+%{time:format}	- means current time in format that you want
+					(supports all formats supported by go package "time")
+%{level}		- means level name (upper case) of log message ("ERROR", "DEBUG", etc)
+%{lvl}			- means first 3 letters of level name (upper case) of log message ("ERR", "DEB", etc)
+%{file} 		- means name of file in what you wanna write log
+%{filename}		- means the same as %{file}
+%{line}			- means line number of file in what you wanna write log
+%{message}		- means your log message
+```
+Non-existent verbs (like ```%{nonex-verb}``` or ```%{}```) will be replaced by an empty string.
+Invalid verbs (like ```%{inv-verb```) will be treated as plain text.
+
 # Example
 
 Example [program](examples/example.go) demonstrates how to use the logger.
 
-[![Example Output](examples/example.png)](examples/example.go)
 
 ```go
 package main
@@ -20,8 +62,8 @@ import (
 )
 
 func main () {
-	// Get the instance for logger class, "test" is the module name, 1 is used to 
-	// state if we want coloring 
+	// Get the instance for logger class, "test" is the module name, 1 is used to
+	// state if we want coloring
 	// Third option is optional and is instance of type io.Writer, defaults to os.Stderr
 	log, err := logger.New("test", 1, os.Stdout)
 	if err != nil {
@@ -48,6 +90,14 @@ func main () {
 	log.InfoF("This is %s!", "Info")
 
 	log.StackAsError("Message before printing stack");
+
+	// Show warning with format
+	log.SetFormat("[%{module}] [%{level}] %{message}")
+	log.Warning("This is Warning!") // output: "[test] [WARNING] This is Warning!"
+	// Also you can set your format as default format for all new loggers
+	logger.SetDefaultFormat("%{message}")
+	log2, _ := logger.New("pkg", 1, os.Stdout)
+	log2.Error("This is Error!") // output: "This is Error!"
 }
 ```
 

examples/example.go

@@ -27,18 +27,6 @@ func main () {
 	log.Info("This is Info!")
 
 	// Show warning with format message
-	// Verbs:
-	// %{id} - number of msg
-	// %{time} - time with format 2006-01-02 15:04:05
-	//		%{time:format} - time with specified format
-	// %{module} - module name
-	// %{file} or %{filename} - filename
-	// %{line} - line number in file
-	// %{level} or %{lvl} - log level
-	//		%{lvl} - print only 3 first letters of log level
-	//		for example: DEB, WAR, etc
-	//		%{level} - print full name of log level
-	//	%{message} - log message
 	log.SetFormat("[%{module}] [%{level}] %{message}")
 	log.Warning("This is Warning!")
 	// Also you can set your format as default format for all new loggers