Don't give performance gain estimates that appear to be more precise
than they really are, especially when they are wrong
(2/(1/1.15 + 1) = ca. 1.0698).
[Richard Levitte]
*) New function BN_mod_exp_mont_word for small bases (roughly 15-20%
- faster than BN_mod_exp_mont, i.e. 7.5-10% for a full DH exchange).
+ faster than BN_mod_exp_mont, i.e. 7-10% for a full DH exchange).
[Bodo Moeller]
*) CygWin32 support.