remove element selectors

[tsargent]

I think @lovisaNamely and @HipsterBrown have been advocating this, but just an issue to keep it on our radar. Should we remove element selectors like these?
https://github.com/namely/namely-ui-css/blob/master/scss/elements/_typography.scss#L44-L49

... leaving us with just the .class selectors?

[HipsterBrown]

I was focused more more input fields and form selectors, which is where a lot of the strict overrides tend to happen. However, I could see where removing all element selectors helps with consistent usage of the utilities.

[lovisaNamely]

I want to remove all of those element selectors, yes 😄