Added a lint-fraction-readability flag to the configuration

clippy_lints/src/utils/conf.rs

@@ -170,6 +170,8 @@ define_Conf! {
     (warn_on_all_wildcard_imports, "warn_on_all_wildcard_imports": bool, false),
     /// Lint: DISALLOWED_METHOD. The list of blacklisted methods to lint about. NB: `bar` is not here since it has legitimate uses
     (disallowed_methods, "disallowed_methods": Vec<String>, Vec::<String>::new()),
+    /// Lint: UNREADABLE_LITERAL. Should the fraction of a decimal be linted to include separators.
+    (lint_fraction_readability, "lint_fraction_readability": bool, true),
 }
 
 impl Default for Conf {