Add rustfmt.toml file with reasonable rules

rustfmt.toml

@@ -1,68 +1,9 @@
-# Config file for cargo fmt. Uncomment line to edit the default settings.
-
-# max_width = 100
-# hard_tabs = false
-# tab_spaces = 4
-# newline_style = "Auto"
-# use_small_heuristics = "Default"
-# indent_style = "Block"
-# wrap_comments = true
-#format_code_in_doc_comments = true
-#comment_width = 80
-# normalize_comments = true
-# normalize_doc_attributes = true
-# license_template_path = ""
-# format_strings = true
-# format_macro_matchers = true
-# format_macro_bodies = true
-# empty_item_single_line = true
-# struct_lit_single_line = true
-# fn_single_line = false
-# where_single_line = false
-# imports_indent = "Block"
-# imports_layout = "Mixed"
-# merge_imports = false
-# reorder_imports = true
-# reorder_modules = true
-# reorder_impl_items = false
-# type_punctuation_density = "Wide"
-# space_before_colon = false
-# space_after_colon = true
-# spaces_around_ranges = false
-# binop_separator = "Front"
-# remove_nested_parens = true
-# combine_control_expr = true
-# overflow_delimited_expr = false
-# struct_field_align_threshold = 0
-# enum_discrim_align_threshold = 0
-# match_arm_blocks = true
-# force_multiline_blocks = false
-# fn_args_layout = "Tall"
-# brace_style = "SameLineWhere"
-# control_brace_style = "AlwaysSameLine"
-# trailing_semicolon = true
-# trailing_comma = "Vertical"
-# match_block_trailing_comma = false
-# blank_lines_upper_bound = 1
-# blank_lines_lower_bound = 0
-edition = "2018"
-# version = "One"
-# inline_attribute_width = 0
-# merge_derives = true
-# use_try_shorthand = false
-# use_field_init_shorthand = false
-# force_explicit_abi = true
-# condense_wildcard_suffixes = false
-# color = "Auto"
-# required_version = "1.4.21"
-# unstable_features = false
-# disable_all_formatting = false
-# skip_children = false
-# hide_parse_errors = false
-# error_on_line_overflow = false
-# error_on_unformatted = false
-# report_todo = "Never"
-# report_fixme = "Never"
-# ignore = []
-# emit_mode = "Files"
-# make_backup = false
+reorder_imports = true
+imports_granularity = "Crate"
+use_small_heuristics = "Max"
+comment_width = 100
+wrap_comments = true
+binop_separator = "Back"
+trailing_comma = "Vertical"
+trailing_semicolon = false
+use_field_init_shorthand = true