feat(#5): add @media print css stuff

[vogloblinsky]

I need to print the agenda page for personal stuff, so i share the code.

• fixes default Material Design Lite @media print cleanings
• first for agenda page
• quickly tested on other pages (stuff still remains)

[jlandure]

Thx @vogloblinsky for the PR 👍

[vogloblinsky]

You're welcome