Added Material Clock widget

[quenbyako]

Tried to make something cool, so it is! I'm new guy in flutter, and want to take feedback about, am i doing right this... Stuff?

Have i read How to contribute? Of course i did! 🌝🌝🌝

Of course i'll add this bage after you will close this pull request

[Solido]

Hey a really cool widget but not really integrable in an app.
Send us a PR with your next creation ! Thank you.

[quenbyako]

@Solido Okay, if i improve this repo, will you add it into the list? If yes, i'm starting right now)

[Solido]

The goal of the list is to curate the most useable resources for developers.
A clock is cool but not useful in an app.
What's cool is that there a LOT of required solutions that need implementations.
Find something that everyone need !