Merge #720: rustfmt: Use show_parse_errors

dc3fc09 rustfmt: Use show_parse_errors (Tobin C. Harding)

Pull request description:

  Clear deprecation warning by using the new option.

ACKs for top commit:
  apoelstra:
    ACK dc3fc09 successfully ran local tests

Tree-SHA512: 3277d832d71a8d9ca773c1a0dd54ca79435c703a80994b3512c5a781b1a4e56ecf21639d9e0bc12b60b984b4ccf2201c532b4c7df52c012e1f507f8d0bc607b8

Author: apoelstra

rustfmt.toml

@@ -74,7 +74,7 @@ color = "Auto"
 unstable_features = false
 disable_all_formatting = false
 skip_children = false
-hide_parse_errors = false
+show_parse_errors = true
 error_on_line_overflow = false
 error_on_unformatted = false
 emit_mode = "Files"