message: doc: fix typos and wording
  In particular, "proceding" should be "following."
  PR
diff: @@ -679,7 +679,7 @@ impl<'a> Fsm<'a> {
  }
  } else if next_si & STATE_START > 0 {
  // A start state isn't in the common case because we may
  - // what to do quick prefix scanning. If the program doesn't
  + // want to do quick prefix scanning. If the program doesn't
  // have a detected prefix, then start states are actually
  // considered common and this case is never reached.
  debug_assert!(self.has_prefix());
  @@ -725,7 +725,7 @@ impl<'a> Fsm<'a> {
  }
  }
  - // Run the DFA once more on the special EOF senitnel value.
  + // Run the DFA once more on the special EOF sentinel value.
  // We don't care about the special bits in the state pointer any more,
  // so get rid of them.
  prev_si &= STATE_MAX;
  @@ -830,7 +830,7 @@ impl<'a> Fsm<'a> {
  }
  }
  - // Run the DFA once more on the special EOF senitnel value.
  + // Run the DFA once more on the special EOF sentinel value.
  prev_si = match self.next_state(qcur, qnext, prev_si, Byte::eof()) {
  None => return Result::Quit,
  Some(STATE_DEAD) => return result.set_non_match(0),
  @@ -913,8 +913,8 @@ impl<'a> Fsm<'a> {
  if self.state(si).flags().has_empty() {
  // Compute the flags immediately preceding the current byte.
  // This means we only care about the "end" or "end line" flags.
  - // (The "start" flags are computed immediately proceding the
  - // current byte and is handled below.)
  + // (The "start" flags are computed immediately following the
  + // current byte and are handled below.)
  let mut flags = EmptyFlags::default();
  if b.is_eof() {
  flags.end = true;
  @@ -1048,7 +1048,7 @@ impl<'a> Fsm<'a> {
  ///
  /// If matching starts after the beginning of the input, then only start
  /// line should be set if the preceding byte is `\n`. End line should never
  - /// be set in this case. (Even if the proceding byte is a `\n`, it will
  + /// be set in this case. (Even if the following byte is a `\n`, it will
  /// be handled in a subsequent DFA state.)
  fn follow_epsilons(
  &mut self,
  