TX queue gas limit config and allow local transactions over the gas limit (#2553)

* Gas limit config; Allow local transactions over the limit

* Fix typo

[ci:skip]

parity/cli/config.full.toml

@@ -68,6 +68,7 @@ price_update_period = "hourly"
 gas_floor_target = "4700000"
 gas_cap = "6283184"
 tx_queue_size = 2048
+tx_queue_gas = "auto"
 tx_gas_limit = "6283184"
 extra_data = "Parity"
 remove_solved = false

parity/cli/config.toml

@@ -41,6 +41,7 @@ reseal_on_txs = "all"
 reseal_min_period = 4000
 price_update_period = "hourly"
 tx_queue_size = 2048
+tx_queue_gas = "auto"
 
 [footprint]
 tracing = "on"

parity/cli/mod.rs

@@ -195,6 +195,8 @@ usage! {
 			or |c: &Config| otry!(c.mining).extra_data.clone().map(Some),
 		flag_tx_queue_size: usize = 2048usize,
 			or |c: &Config| otry!(c.mining).tx_queue_size.clone(),
+		flag_tx_queue_gas: String = "auto",
+			or |c: &Config| otry!(c.mining).tx_queue_gas.clone(),
 		flag_remove_solved: bool = false,
 			or |c: &Config| otry!(c.mining).remove_solved.clone(),
 		flag_notify_work: Option<String> = None,
@@ -348,6 +350,7 @@ struct Mining {
 	gas_cap: Option<String>,
 	extra_data: Option<String>,
 	tx_queue_size: Option<usize>,
+	tx_queue_gas: Option<String>,
 	remove_solved: Option<bool>,
 	notify_work: Option<Vec<String>>,
 }
@@ -523,6 +526,7 @@ mod tests {
 			flag_gas_cap: "6283184".into(),
 			flag_extra_data: Some("Parity".into()),
 			flag_tx_queue_size: 2048usize,
+			flag_tx_queue_gas: "auto".into(),
 			flag_remove_solved: false,
 			flag_notify_work: Some("http://localhost:3001".into()),
 
@@ -673,6 +677,7 @@ mod tests {
 				gas_floor_target: None,
 				gas_cap: None,
 				tx_queue_size: Some(2048),
+				tx_queue_gas: Some("auto".into()),
 				tx_gas_limit: None,
 				extra_data: None,
 				remove_solved: None,

parity/cli/usage.txt

@@ -184,6 +184,10 @@ Sealing/Mining Options:
                            more than 32 characters. (default: {flag_extra_data:?})
   --tx-queue-size LIMIT    Maximum amount of transactions in the queue (waiting
                            to be included in next block) (default: {flag_tx_queue_size}).
+  --tx-queue-gas LIMIT     Maximum amount of total gas for external transactions in
+                           the queue. LIMIT can be either an amount of gas or
+                           'auto' or 'off'. 'auto' sets the limit to be 2x
+                           the current block gas limit. (default: {flag_tx_queue_gas}).
   --remove-solved          Move solved blocks from the work package queue
                            instead of cloning them. This gives a slightly
                            faster import speed, but means that extra solutions