[How to create a new Bridge?] Add new page

How-to-create-a-new-Bridge?.md

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+Create a new file in the `bridges/` folder (see [Folder structure](Folder-structure)).
+
+The file name begins with the name of the site, followed by the word 'Bridge' and the file type PHP. 
+
+**Examples:**
+
+Site | Filename
+-----|---------
+Wikipedia | **Wikipedia**Bridge.php
+Facebook | **Facebook**Bridge.php
+GitHub | **GitHub**Bridge.php
+
+The file must start with the PHP tags and end with an empty line. The closing tag `?>` is [omitted](http://php.net/basic-syntax.instruction-separation). 
+
+**Example:**
+
+```PHP
+<?PHP
+	// PHP code here
+// This line is empty (just imagine it!)
+```
+
+The next step is to extend one of the base classes. Refer to one of an base classes listed on the [Bridge API](Bridge-API) page.