Add grandpa telemetry (+ other minor improvements) (#1997)

* Support skipping the interactive purge prompt

Skip it via `cargo run -- purge-chain -y`.

* Fix typos

* Add Grandpa telemetry

* Address comments

* Revert unnecessary version bump

* Version bump to make CI run

* Remove unnecessary cast

* Do not bump version

substrate/srml/support/src/dispatch.rs

@@ -30,7 +30,7 @@ pub use srml_metadata::{
 /// A type that can not be instantiated.
 pub enum Never {}
 
-/// Result of a module function call; either nothing (functions are only called for "side efeects")
+/// Result of a module function call; either nothing (functions are only called for "side effects")
 /// or an error message.
 pub type Result = result::Result<(), &'static str>;
 

substrate/srml/support/src/double_map.rs

@@ -121,7 +121,7 @@ pub trait StorageDoubleMap {
 	fn derive_key2(key2_data: Vec<u8>) -> Vec<u8>;
 
 	/// Returns a compound key that consist of the two parts: (prefix, `k1`) and `k2`.
-	/// The first part is hased and then concatenated with a hash of `k2`.
+	/// The first part is hashed and then concatenated with a hash of `k2`.
 	fn full_key<Q, R>(k1: &Q, k2: &R) -> Vec<u8>
 	where
 		Self::Key1: Borrow<Q>,

substrate/srml/support/src/event.rs

@@ -67,7 +67,7 @@ pub use srml_metadata::{EventMetadata, DecodeDifferent, OuterEventMetadata, FnEn
 ///
 /// mod event2 {
 ///     // Event that uses the generic parameter `Balance`.
-///     // If no name for the generic parameter is speciefied explicitly,
+///     // If no name for the generic parameter is specified explicitly,
 ///     // the name will be taken from the type name of the trait.
 ///     decl_event!(
 ///	       pub enum Event<T> where <T as super::Trait>::Balance {

substrate/srml/support/src/traits.rs

@@ -176,7 +176,7 @@ pub trait Currency<AccountId> {
 /// they can be individually replaced or removed.
 pub type LockIdentifier = [u8; 8];
 
-/// A currency whose accounts can have liquidity restructions.
+/// A currency whose accounts can have liquidity restrictions.
 pub trait LockableCurrency<AccountId>: Currency<AccountId> {
 	/// The quantity used to denote time; usually just a `BlockNumber`.
 	type Moment;
@@ -210,7 +210,7 @@ pub trait LockableCurrency<AccountId>: Currency<AccountId> {
 /// Charge bytes fee trait
 pub trait ChargeBytesFee<AccountId> {
 	/// Charge fees from `transactor` for an extrinsic (transaction) of encoded length
-	/// `encoded_len` bytes. Return Ok iff the payment was successful.
+	/// `encoded_len` bytes. Return Ok if the payment was successful.
 	fn charge_base_bytes_fee(transactor: &AccountId, encoded_len: usize) -> Result<(), &'static str>;
 }
 
@@ -222,7 +222,7 @@ pub trait ChargeFee<AccountId>: ChargeBytesFee<AccountId> {
 	/// Charge `amount` of fees from `transactor`. Return Ok iff the payment was successful.
 	fn charge_fee(transactor: &AccountId, amount: Self::Amount) -> Result<(), &'static str>;
 
-	/// Refund `amount` of previous charged fees from `transactor`. Return Ok iff the refund was successful.
+	/// Refund `amount` of previous charged fees from `transactor`. Return Ok if the refund was successful.
 	fn refund_fee(transactor: &AccountId, amount: Self::Amount) -> Result<(), &'static str>;
 }