removing whitespace all over

xml.html.markdown

@@ -38,10 +38,10 @@ Unlike HTML, XML does not specify how to display or to format data, just carry i
 
 <!-- Above is a typical XML file.
   It starts with a declaration, informing some metadata (optional).
-  
+
   XML uses a tree structure. Above, the root node is 'bookstore', which has
-  three child nodes, all 'books'. Those nodes has more child nodes, and so on... 
-  
+  three child nodes, all 'books'. Those nodes has more child nodes, and so on...
+
   Nodes are created using open/close tags, and childs are just nodes between
   the open and close tags.-->
 
@@ -54,8 +54,8 @@ Unlike HTML, XML does not specify how to display or to format data, just carry i
   2 - Elements -> That's pure data.
       That's what the parser will retrieve from the XML file.
       Elements appear between the open and close tags. -->
-      
-  
+
+
 <!-- Below, an element with two attributes -->
 <file type="gif" id="4293">computer.gif</file>
 
@@ -68,14 +68,14 @@ A XML document is well-formated if it is syntactically correct.
 However, it is possible to inject more constraints in the document,
 using document definitions, such as DTD and  XML Schema.
 
-A XML document which follows a document definition is called valid, 
-regarding that document. 
+A XML document which follows a document definition is called valid,
+regarding that document.
 
 With this tool, you can check the XML data outside the application logic.
 
 ```xml
 
-<!-- Below, you can see an simplified version of bookstore document, 
+<!-- Below, you can see an simplified version of bookstore document,
   with the addition of DTD definition.-->
 
 <?xml version="1.0" encoding="UTF-8"?>