Minimize preflight

[sdavids]

Please minify the preflight also.

Let's say we only use <h1> and not the other ones then this:

tailwindcss/src/css/preflight.css

Lines 76 to 84 in e5eceb3

	h1,
	h2,
	h3,
	h4,
	h5,
	h6 {
	font-size: inherit;
	font-weight: inherit;
	}

could be reduced to:

h1 { 
  font-size: inherit; 
  font-weight: inherit; 
} 

Similarly if one does not use <small> then this could be removed:

tailwindcss/src/css/preflight.css

Lines 125 to 127 in e5eceb3

	small {
	font-size: 80%;
	}

Yes, one can turn it off completely and provide one's own version but in that case one would not get the improvements made to the preflight by the Tailwind team.