Registrar and contractInfo handling

* resolver -> common/registrar
  * global registrar name registry interface
  * add Call to resolver backend interface
  * the hashReg and UrlHing contracts now initialised from global registry
  * initialization of contracts uniform
  * improve errors and more econsistent method names
* common/registrar/ethreg: versioned registrar
* integrate new naming and registrar in natspec
* js console api: setGlobalRegistrar, setHashReg, setUrlHint
* js test TestContract uses mining - tests fixed all pass
* eth/backend: allow PoW test mode (small ethash DAG)
* console jsre refers to resolver.abi/addr,
* cmd/geth/contracts.go moved to common/registrar

cmd/geth/blocktestcmd.go

@@ -86,7 +86,6 @@ func runBlockTest(ctx *cli.Context) {
 }
 
 func runOneBlockTest(ctx *cli.Context, test *tests.BlockTest) (*eth.Ethereum, error) {
-	// TODO remove in favor of logic contained in tests package
 	cfg := utils.MakeEthConfig(ClientIdentifier, Version, ctx)
 	cfg.NewDB = func(path string) (common.Database, error) { return ethdb.NewMemDatabase() }
 	cfg.MaxPeers = 0 // disable network