Extend Template widget

Based on SQL Queries widget, this adds param_count, memory_str, type and
expandable params, as proposed in #114
This shouldn't break anything, just add more information if supplied.

This makes it a bit more flexible. Not sure if param_count, memory and type are the correct ones (next to render_time), but I use params right now (duration/memory not yet). Type is for example to show if it's twig/blade/phtml etc.

@maximebf more suggestions to show?