Warn if blockchain majority doesn't match CBlock::CURRENT_VERSION
Warn if blockchain majority doesn't match CBlock::CURRENT_VERSION

This adds a warning "this version is obsolete, upgrade required" if
more than 50 of the previous 100 blocks in the blockchain are
a new version.

Cannacoin-Project/Cannacoin,bmp02050/ReddcoinUpdates,reddink/reddcoin,reddink/reddcoin,bmp02050/ReddcoinUpdates,joroob/reddcoin,reddcoin-project/reddcoin,joroob/reddcoin,reddcoin-project/reddcoin,reddink/reddcoin,ahmedbodi/poscoin,reddcoin-project/reddcoin,coinkeeper/2015-06-22_19-10_cannacoin,ahmedbodi/poscoin,joroob/reddcoin,coinkeeper/2015-06-22_18-46_reddcoin,coinkeeper/2015-06-22_18-46_reddcoin,bmp02050/ReddcoinUpdates,reddcoin-project/reddcoin,bmp02050/ReddcoinUpdates,reddink/reddcoin,reddink/reddcoin,coinkeeper/2015-06-22_18-46_reddcoin,ahmedbodi/poscoin,coinkeeper/2015-06-22_18-46_reddcoin,Cannacoin-Project/Cannacoin,coinkeeper/2015-06-22_19-10_cannacoin,reddcoin-project/reddcoin,ahmedbodi/poscoin,Cannacoin-Project/Cannacoin,Cannacoin-Project/Cannacoin,joroob/reddcoin,Cannacoin-Project/Cannacoin,reddcoin-project/reddcoin,bmp02050/ReddcoinUpdates,coinkeeper/2015-06-22_18-46_reddcoin,coinkeeper/2015-06-22_19-10_cannacoin,coinkeeper/2015-06-22_19-10_cannacoin,coinkeeper/2015-06-22_19-10_cannacoin,joroob/reddcoin,ahmedbodi/poscoin