Font Awesome 5 support

Hi! I would really love if you could make a small change to support Font Awesome version 5. The difference from version 4 is that now they generate a svg-tag instead of using the font-family.

Example Version 4: <i aria-hidden="true" class="fa fa-caret-down"></i> & with the css looking something like this: .fa-caret-down:before { font-family: FontAwesome; content: "\f107"; }

Version 5: <svg aria-hidden="true" class="svg-inline--fa fa-caret-down fa-w-10" data-prefix="fa" data-icon="caret-down" role="img"> <path fill="currentColor" d="M31.3 192h257.3c17........"></path> </svg> <!-- <i aria-hidden="true" class="fa fa-caret-down"></i> -->

So they´re commenting away the <i></i> tag when generating the svg, which leads to that the carets in your treeview is not working.

Thanks for your quick support.

[nheath99]

@leovo2708 I agree with @ida-e, this is fully compatible with FontAwesome 4.

[nheath99]

Thanks. It is very simple; I have created a pull request: #151 I have also changed lines 32-33 with the same principles. Please add any comments.