Use rooted bank by default in rpc bank selection (#6759)

* Name anonymous parameters for clarity

* Add CommitmentConfig to select bank for rpc

* Add commitment information to jsonrpc docs

* Update send_and_confirm retries as per commitment defaults

* Pass CommitmentConfig into client requests; also various 'use' cleanup

* Use _with_commitment methods to speed local_cluster tests

* Pass CommitmentConfig into Archiver in order to enable quick confirmations in local_cluster tests

* Restore solana ping speed

* Increase wallet-sanity timeout to account for longer confirmation time

sdk/src/commitment_config.rs

@@ -0,0 +1,36 @@
+#[derive(Serialize, Deserialize, Clone, Debug, PartialEq)]
+#[serde(rename_all = "camelCase")]
+pub struct CommitmentConfig {
+    pub commitment: CommitmentLevel,
+}
+
+impl Default for CommitmentConfig {
+    fn default() -> Self {
+        CommitmentConfig {
+            commitment: CommitmentLevel::Max,
+        }
+    }
+}
+
+impl CommitmentConfig {
+    pub fn recent() -> Self {
+        Self {
+            commitment: CommitmentLevel::Recent,
+        }
+    }
+
+    pub fn ok(&self) -> Option<Self> {
+        if self == &Self::default() {
+            None
+        } else {
+            Some(self.clone())
+        }
+    }
+}
+
+#[derive(Serialize, Deserialize, Clone, Debug, PartialEq)]
+#[serde(rename_all = "camelCase")]
+pub enum CommitmentLevel {
+    Max,
+    Recent,
+}