New color theme Homunculus.theme

Low-contrast theme like solarized, but without too much yellowish and keep enough contrast between code and background.

Partially inspired by

• https://protesilaos.com/emacs/modus-themes
• https://github.com/nashamri/spacemacs-theme
• https://earl-grey.halt.wtf

I want to hear what other people might think, so I want to post it somewhere and polish a bit more before merge.

Please feel free to criticize or reject :)