Change "Docs" to "Learn"

[Geokureli]

I feel like people don't know where to start, and this will attract newcomers, more

[ninjamuffin99]

this is good idea 👍

one thing I think to sorta make sure of, if we change URLs (haxeflixel.com/documentation -> haxelfixel.com/learn) is making sure we have proper redirects setup I think!
However an easy/lazy way, we can just change the Docs onsite to just say Learn, and keep the url saying "documentation/" lol

[Geokureli]

I'm fine with keeping the url, if you are