[docs] Add redirects for docs urls that end in /null for some reason
[docs] Add redirects for docs urls that end in /null for some reason

exponentjs/exponent,exponentjs/exponent,exponent/exponent,exponent/exponent,exponent/exponent,exponentjs/exponent,exponent/exponent,exponent/exponent,exponent/exponent,exponent/exponent,exponent/exponent,exponentjs/exponent,exponentjs/exponent,exponentjs/exponent,exponent/exponent,exponentjs/exponent,exponentjs/exponent,exponentjs/exponent