Formatting fixes + some tiny UX enhancements.

• ADD - new Html.tooltip builder
• ADD - option to control the positioning of the tooltip, relatively to the center of the parent element (implied some changes in the css)
• FIX - width values/unit for the tooltips width, using em instead of px.
• ADD - Ctrl+I kb shortcut to terminals, to toggle the public tests
• ADD - Clicking on play/validation button gives the focus to the terminal, once everything is done (allow to use all the shortcuts after that).
• FIX - a non ASCII char was showing up on "sol/rem revelation", when there was neither corr.py nor REM.md
• FIX - the bit mask defining the presence of corr and/or rem was defined backward in the IDE macros
• FIX - Enhance dev_docs to tests the combinations of presence/absence of corr/rem