skills update: freemarker, vanilla js

[Ingo Steinke]

add skills searched or requested by specific project requirements;
rearrange colors accordingly;
"Vanilla/VanillaJS": closest color would be floralwhite = #fffaf0, needs a border to still look like a tile;
remove "Preact", move React and Vanilla to the end of the line;
add "Freemarker" which has a color close to the React brand, possibly after Markdown for a nicer color row;
remove "XML" (too generic) to gain the necessary space;
PHP row: move Symfony after PHP 8 for various reasons or rather a gut feeling;