Merge remote-tracking branch 'upstream/master' into terracoin
Merge branch 'master' into release-0.1.3
release branch marked as such.
Merge branch 'release-0.1.3' into dev-0.1.3
Merge branch 'master' into release-0.1.3
Merge branch 'release-0.1.3' into dev-0.1.3
Merge branch 'master' into release-0.1.3
Merge branch 'release-0.1.3' into dev-0.1.3
Merge remote-tracking branch 'terracoin/master' into terracoin
211.147.4.0 - 211.147.7.255 netblock banned.
Merge branch 'master' into release-0.1.3
Merge branch 'release-0.1.3' into dev-0.1.3
testnet: restored simple retargetting mechanism.

 - invalidates previous  testnet blocks
 - testnet checkpoints updated
 - testnet seednodes updated.
testnet: switch to simple retargetting.

 - note that testnet uses really small windows for computing new target.
   this may be cheated, but livenet will use longer windows preventing
   this.
testnet: switched back to a bitcoin-like retargetting window.
comments and logging.
checkpoint added.
logging
testnet: last ema attempt

 - new targets now limited to 1% change max
 - now measures individual block duration over last N blocks (90 for
   testnet)
 - averaged input data reduced to +/- 10% (108/120/132) ; should allow
   faster adjustments over time, by reducing "waves" height, especially
   when combined with above pre-averaging.
testnet: averaged block range timespan.

 - quick & dirty push for remote tester