Create xml_parser.cpp

A simple xml parser which prints your xml file in the following format(output):
-------------------------
Parsing succeeded
-------------------------
tag: foo
{
        tag: bar
        {
                text: bar 1
        }
        tag: bar
        {
                text: bar 2
        }
        tag: bar
        {
                text: bar 3
        }
}

xml file(input):
<foo>
    <bar>bar 1</bar>
    <bar>bar 2</bar>
    <bar>bar 3</bar>
</foo>