Add comments improvements

contracts/sfc/NodeDriverAuth.sol

@@ -63,7 +63,7 @@ contract NodeDriverAuth is OwnableUpgradeable, UUPSUpgradeable {
     }
 
     /// Execute a batch update of network configuration.
-    /// Run given contract with a permission of the NodeDriverAuth owner.
+    /// The executable will run with the privileges of the NodeDriverAuth owner.
     /// Does not allow changing NodeDriver and NodeDriverAuth code.
     function execute(address executable) external onlyOwner {
         _execute(executable, owner(), _getCodeHash(address(this)), _getCodeHash(address(driver)));
@@ -89,7 +89,7 @@ contract NodeDriverAuth is OwnableUpgradeable, UUPSUpgradeable {
         driver.setBalance(acc, address(acc).balance + diff);
     }
 
-    /// Upgrade code of given contract by coping it from other deployed contract.
+    /// Upgrade code of given contract by copying it from other deployed contract.
     /// Avoids setting code to an external address.
     function upgradeCode(address acc, address from) external onlyOwner {
         if (!isContract(acc) || !isContract(from)) {
@@ -98,7 +98,7 @@ contract NodeDriverAuth is OwnableUpgradeable, UUPSUpgradeable {
         driver.copyCode(acc, from);
     }
 
-    /// Upgrade code of given contract by coping it from other deployed contract.
+    /// Upgrade code of given contract by copying it from other deployed contract.
     /// Does not avoid setting code to an external address. (DANGEROUS!)
     function copyCode(address acc, address from) external onlyOwner {
         driver.copyCode(acc, from);

contracts/sfc/SFC.sol

@@ -273,7 +273,7 @@ contract SFC is OwnableUpgradeable, UUPSUpgradeable, Version {
     }
 
     /// Accept redirection proposal.
-    /// Redirection must by accepted by the validator key holder before it start to be applied.
+    /// Redirection must by accepted by the validator key holder before it starts to be applied.
     function redirect(address to) external {
         address from = msg.sender;
         if (to == address(0)) {