Add documentation for v1.1.0

documentation/UserGuide.md

@@ -7,6 +7,7 @@ Users can configure the way the logger works and the image will use this configu
 For specific cases, a specialized logger can be used.
 
 - [User documentation of TinyLogger](#user-documentation-of-tinylogger)
+  * [Quick start](#quick-start)
   * [Configure your logger](#configure-your-logger)
     + [Add sub-loggers to your `TinyLogger`](#add-sub-loggers-to-your--tinylogger-)
     + [Remove sub-loggers](#remove-sub-loggers)
@@ -16,6 +17,40 @@ For specific cases, a specialized logger can be used.
     + [Record a single line log](#record-a-single-line-log)
     + [Recording the execution of a task](#recording-the-execution-of-a-task)
   * [Use another logger than the global logger](#use-another-logger-than-the-global-logger)
+
+## Quick start
+
+This section will explain in 30 seconds how to create a logger for an application and use it. Then we will explore more advance features.
+
+Here is an example fo snippet to create a logger using a file `Progress.log`:
+
+```Smalltalk
+TinyLogger default 
+    addFileLoggerNamed: 'Progress.log'.
+```
+
+This code need to be executed **one time** in the image. For an application, it will probably be added to a method *initialize* on the class side of a class to be executed one time at the loading of the project in the image.
+
+In case you need to execute the code multiple times you can use this snippet instead:
+
+```Smalltalk
+TinyLogger default 
+    ensureFileLoggerNamed: 'Progress.log'.
+```
+
+Then write a message to the log using `record`:
+
+```Smalltalk
+'Uh oh. Something happened.' record
+```
+
+Or wrap the execution of an action by logs using `execute:recordedAs:`:
+
+```Smalltalk
+self execute: [ "Some code doing something" ] recordedAs: 'Launching bananas.'
+```
+
+Now, if you want to know more about the project, let's proceed on a more detailed documentation.
 
 ## Configure your logger
 
@@ -50,6 +85,19 @@ TinyLogger default
 	addFileLoggerNamed: '../logs/MyOtherLog.log'.
 ```
 
+Additionaly to those methods, `TinyLogger` also propose ways to add loggers only if they have no equivalent already registered.
+
+In order to archieve this result, you can use the equivalent of the methods previously explained, replacing `add` by `ensure`:
+```Smalltalk
+TinyLogger default
+	ensureStdoutLogger;
+	ensureTranscriptLogger;
+	ensureFileLogger;
+	ensureFileLoggerNamed: '../logs/MyOtherLog.log'.
+```
+
+With those methods, Transcript and Stdout loggers will be limited to one, and file loggers will be limited to one by file name.
+
 ### Remove sub-loggers
 
 If at some point you wants to remove one or multiple loggers, `TinyLogger` has some API elements to do that.