EIP-3554: Ice Age delay targeting December 2021

I backtested for all of the times the difficulty bomb was first visible.

#First bomb sight May 1st 2017  (Coeff = 0.10)
#diff_adjust_coeff = predict_diff_bomb_effect(3630000,336173000000000,0,0)

#Second Bomb Sighting Dec 20th 2018 (Coeff=0.12)
#diff_adjust_coeff = predict_diff_bomb_effect(6920000,2263365000000000,3000000,0)

#Third Bomb Sighting Nov 10th 2019 (Coeff=0.11)
#diff_adjust_coeff = predict_diff_bomb_effect(8910000,2532534000000000,5000000,0)

This confirms the bomb should be seen when the Coeff reaches 0.1