re-organizing to function like ed25519-donna
only limbs 0-3 _need_ to be reduced for subs (but do a few more anyway)
replace some magic constants with named variables
replaced magic constants with named variables
simply writing out the final value as we are know sse2 is little endian
tweak to take advantage of the curve25519 fixed exponent positions (bit 255 is 0, 254 is 1, and 0-2 are 0)
add --out parameter to fuzz builder
handle points with the 256th bit set the same as the ref impl
test shared secret generation
update readmes