Update changelog formatting

CHANGELOG.mdown

@@ -1,4 +1,4 @@
-* 1.4.0 (2013-02-13)
+### 1.4.0 (2013-02-13)
 
   * Added RedisHandler to log to Redis via the Predis library or the phpredis extension
   * Added ZendMonitorHandler to log to the Zend Server monitor
@@ -7,12 +7,12 @@
   * Fixed ChromePHPHandler and FirePHPHandler issue when multiple instances are used simultaneously
   * Fixed header injection capability in the NativeMailHandler
 
-* 1.3.1 (2013-01-11)
+### 1.3.1 (2013-01-11)
 
   * Fixed LogstashFormatter to be usable with stream handlers
   * Fixed GelfMessageFormatter levels on Windows
 
-* 1.3.0 (2013-01-08)
+### 1.3.0 (2013-01-08)
 
   * Added PSR-3 compliance, the `Monolog\Logger` class is now an instance of `Psr\Log\LoggerInterface`
   * Added PsrLogMessageProcessor that you can selectively enable for full PSR-3 compliance
@@ -26,12 +26,12 @@
     the oldest entries
   * Fixed normalization of objects with cyclic references
 
-* 1.2.1 (2012-08-29)
+### 1.2.1 (2012-08-29)
 
   * Added new $logopts arg to SyslogHandler to provide custom openlog options
   * Fixed fatal error in SyslogHandler
 
-* 1.2.0 (2012-08-18)
+### 1.2.0 (2012-08-18)
 
   * Added AmqpHandler (for use with AMQP servers)
   * Added CubeHandler
@@ -44,7 +44,7 @@
   * Fixed normalization of exotic resource types
   * Fixed the default format of the SyslogHandler to avoid duplicating datetimes in syslog
 
-* 1.1.0 (2012-04-23)
+### 1.1.0 (2012-04-23)
 
   * Added Monolog\Logger::isHandling() to check if a handler will
     handle the given log level
@@ -57,20 +57,20 @@
   * Added possibility to show microseconds in logs
   * Added `server` and `referer` to WebProcessor output
 
-* 1.0.2 (2011-10-24)
+### 1.0.2 (2011-10-24)
 
   * Fixed bug in IE with large response headers and FirePHPHandler
 
-* 1.0.1 (2011-08-25)
+### 1.0.1 (2011-08-25)
 
   * Added MemoryPeakUsageProcessor and MemoryUsageProcessor
   * Added Monolog\Logger::getName() to get a logger's channel name
 
-* 1.0.0 (2011-07-06)
+### 1.0.0 (2011-07-06)
 
   * Added IntrospectionProcessor to get info from where the logger was called
   * Fixed WebProcessor in CLI
 
-* 1.0.0-RC1 (2011-07-01)
+### 1.0.0-RC1 (2011-07-01)
 
   * Initial release