fix html tags in example usage

[deiwin]

the angle brackets were inverted

[knsv]

Thanks! I don't know how I could miss that ... :)

[deiwin]

By the way, I ended up writing something like this (in coffeescript), to use mermaid with marked:

marked = require 'marked'

module.exports = (options) ->
  hasMermaid = false
  renderer = new marked.Renderer()
  renderer.defaultCode = renderer.code
  renderer.code = (code, language) ->
    if language is 'mermaid'
      html = ''
      if not hasMermaid
        hasMermaid = true
        html += '<script src="'+options.mermaidPath+'"></script>'
      html + '<div class="mermaid">'+code+'</div>'
    else
      @defaultCode(code, language)

  renderer

If you want you can update the example to something similar.

[knsv]

Thanks, will add/uppdate that! Would be nice with a section on different ways to to add mermaid to a workflow.