remove ommer/nibbler reward constants as they can be derived from the block reward

Author: jwasinger

params.json

@@ -229,14 +229,6 @@
     "v": "3000000000000000000",
     "d": "the amount a miner get rewarded for mining a block"
   },
-  "ommerReward": {
-    "v": "625000000000000000",
-    "d": "The amount of wei a miner of an uncle block gets for being inculded in the blockchain"
-  },
-  "niblingReward": {
-    "v": "156250000000000000",
-    "d": "the amount a miner gets for inculding a uncle"
-  },
   "homeSteadForkNumber": {
     "v": 1150000,
     "d": "the block that the Homestead fork started at"