Genesis block for known chains, mine dev chains (#269)

Renamed mining parameter mode to chain type, with existing types
of CI testing, user testing, testnet1 or mainnet. The public
chains (testnet1 and mainnet) come with their fully pre-defined
genesis block.

Still need to set the nonce and cycle for testnet1 genesis.

src/bin/grin.rs

@@ -57,7 +57,7 @@ fn start_from_config_file(mut global_config: GlobalConfig) {
 			.unwrap()
 			.server
 			.clone()
-			.mining_parameter_mode
+			.chain_type
 			.unwrap(),
 	);
 
@@ -102,7 +102,7 @@ fn main() {
 				.unwrap()
 				.server
 				.clone()
-				.mining_parameter_mode
+				.chain_type
 				.unwrap(),
 		);
 	} else {