docs website: plugins list grouping?

[DominiqueMakowski]

This is just a random comment, so feel free to close it and disregard if irrelevant ^^

The plugin list is slightly long and sometimes it adds an extra second or so to find the plugin one is after.
I wonder if it would be helpful to make some subsections:

• Core blocks: plugins for basic In&Out elements: typically image-keyboard, image-mouse, html-button etc. They are the "fundamental" building blocks with which you can create more complex studies.
• Procedures: are more complex routines & procedures, like the IAT, cloze
• Interface: plugins interfacing with other things, like webgazer, initialization of mic & cam, etc.