1.1.8.7-Mandatory Upgrade (@ Block 102,025)

• Fix bug in POG mining algorithm causing too many tithes to enter the
  pog pool per day
• During block heights 100,775-102,024 BiblePay corrects most of the
  overflow effects as a temporary leisure fix
• After block 102,025 (the mandatory deadline cutover height) Biblepay
  upgrades POG to v2.0; this allows thousands of tithes into the pog pool
  per day and corrects the algorithm from overflow effects and prevents
  attacks
• Fix POW difficulty value for POBH in getinfo
• Make POG leaderboard sort by share % descending
• Allow tithe=n (allow any value including 2; 0=off, 1=default, 2-up =
  minutes between tithing)
• Increased PODC vote height to 107,000 (when we vote to retire PODC)