Remove leading backslash in use statements

While it is acceptable syntax, it is unnecessary and not recommended by
the PHP documentation:

https://secure.php.net/manual/en/language.namespaces.importing.php#language.namespaces.importing

> Note that for namespaced names (fully qualified namespace names
> containing namespace separator, such as Foo\Bar as opposed to global
> names that do not, such as FooBar), the leading backslash is
> unnecessary and not recommended, as import names must be fully
> qualified, and are not processed relative to the current namespace.

Readme.md

@@ -55,19 +55,19 @@ autoloading, see below.)
 With class autoloading in place, putting the 'Michelf' folder in your 
 include path should be enough for this to work:
 
-	use \Michelf\Markdown;
+	use Michelf\Markdown;
 	$my_html = Markdown::defaultTransform($my_text);
 
 Markdown Extra syntax is also available the same way:
 
-	use \Michelf\MarkdownExtra;
+	use Michelf\MarkdownExtra;
 	$my_html = MarkdownExtra::defaultTransform($my_text);
 
 If you wish to use PHP Markdown with another text filter function 
 built to parse HTML, you should filter the text *after* the `transform`
 function call. This is an example with [PHP SmartyPants][psp]:
 
-	use \Michelf\Markdown, \Michelf\SmartyPants;
+	use Michelf\Markdown, Michelf\SmartyPants;
 	$my_html = Markdown::defaultTransform($my_text);
 	$my_html = SmartyPants::defaultTransform($my_html);
 
@@ -76,7 +76,7 @@ found inside the parser class. If you want to customize the parser
 configuration, you can also instantiate it directly and change some 
 configuration variables:
 
-	use \Michelf\MarkdownExtra;
+	use Michelf\MarkdownExtra;
 	$parser = new MarkdownExtra;
 	$parser->fn_id_prefix = "post22-";
 	$my_html = $parser->transform($my_text);

Readme.php

@@ -10,7 +10,7 @@ spl_autoload_register(function($class){
 });
 
 // Get Markdown class
-use \Michelf\Markdown;
+use Michelf\Markdown;
 
 // Read file and pass content through the Markdown parser
 $text = file_get_contents('Readme.md');