Add .gitignore, rustfmt and Clippy cfg

Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

.cargo/config.toml

@@ -0,0 +1,32 @@
+#
+# An auto defined `clippy` feature was introduced,
+# but it was found to clash with user defined features,
+# so was renamed to `cargo-clippy`.
+#
+# If you want standard clippy run:
+# RUSTFLAGS= cargo clippy
+[target.'cfg(feature = "cargo-clippy")']
+rustflags = [
+  "-Aclippy::all",
+  "-Dclippy::correctness",
+  "-Aclippy::if-same-then-else",
+  "-Aclippy::clone-double-ref",
+  "-Dclippy::complexity",
+  "-Aclippy::zero-prefixed-literal",     # 00_1000_000
+  "-Aclippy::type_complexity",           # raison d'etre
+  "-Aclippy::nonminimal-bool",           # maybe
+  "-Aclippy::borrowed-box",              # Reasonable to fix this one
+  "-Aclippy::too-many-arguments",        # (Turning this on would lead to)
+  "-Aclippy::unnecessary_cast",          # Types may change
+  "-Aclippy::identity-op",               # One case where we do 0 +
+  "-Aclippy::useless_conversion",        # Types may change
+  "-Aclippy::unit_arg",                  # styalistic.
+  "-Aclippy::option-map-unit-fn",        # styalistic
+  "-Aclippy::bind_instead_of_map",       # styalistic
+  "-Aclippy::erasing_op",                # E.g. 0 * DOLLARS
+  "-Aclippy::eq_op",                     # In tests we test equality.
+  "-Aclippy::while_immutable_condition", # false positives
+  "-Aclippy::needless_option_as_deref",  # false positives
+  "-Aclippy::derivable_impls",           # false positives
+  "-Aclippy::stable_sort_primitive",     # prefer stable sort
+]

.gitignore

@@ -0,0 +1,12 @@
+**/target/
+**/*.rs.bk
+*.swp
+.wasm-binaries
+runtime/wasm/target/
+**/._*
+.idea
+.vscode
+polkadot.*
+!polkadot.service
+.DS_Store
+.env

rustfmt.toml

@@ -0,0 +1,24 @@
+# Basic
+hard_tabs = true
+max_width = 100
+use_small_heuristics = "Max"
+# Imports
+imports_granularity = "Crate"
+reorder_imports = true
+# Consistency
+newline_style = "Unix"
+# Misc
+chain_width = 80
+spaces_around_ranges = false
+binop_separator = "Back"
+reorder_impl_items = false
+match_arm_leading_pipes = "Preserve"
+match_arm_blocks = false
+match_block_trailing_comma = true
+trailing_comma = "Vertical"
+trailing_semicolon = false
+use_field_init_shorthand = true
+ignore = [
+    "bridges",
+]
+edition = "2021"