fix: change hooks component description and fix typos

[einatnielsen]

it's better to avoid "time phrases" in readmes like recently , lately, etc. because who knows, someone might encounter this in a few years, read this and might get confused because he never used class components so he doesn't understand why this note is there... so I changed it to: "Prior to hooks, we were used to writing class components" This wouldn't need to be changed after a "while" has passed.

WDYT?

also I fixes some typos in this PR

[MatanBorenkraoutNielsen]

Yeah that's a good point :) It looks good!