Prism tag is a syntax highligher based on PrismJS.
It produces code blocks like below.
<Prism lang=html> <div class="example">...</div> </Prism>
Note that the immediate new line after the open tag is ignored.
The code inside must not be escaped - for example, no need to replace
Indents are literally passed to the code block.
lang property defines the language of the code.
Currently supported are: