Add example of per-file ignores to the README (#488)

README.md

@@ -95,6 +95,10 @@ select = [
     "F401",
     "F403",
 ]
+per-file-ignores = [
+    "__init__.py:F401",
+    "path/to/file.py:F401"
+]
 ```
 
 Alternatively, on the command-line:

resources/test/fixtures/__init__.py

@@ -1,3 +1,5 @@
+import os
+
 print(__path__)
 
 __all__ = ["a", "b", "c"]

resources/test/fixtures/pyproject.toml

@@ -5,3 +5,6 @@ extend-exclude = [
     "migrations",
     "directory/also_excluded.py",
 ]
+per-file-ignores = [
+    "__init__.py:F401",
+]

src/pyproject.rs

@@ -362,7 +362,10 @@ other-attribute = 1
                 extend_select: vec![],
                 ignore: vec![],
                 extend_ignore: vec![],
-                per_file_ignores: vec![],
+                per_file_ignores: vec![StrCheckCodePair {
+                    pattern: "__init__.py".to_string(),
+                    code: CheckCode::F401
+                }],
                 dummy_variable_rgx: None,
                 target_version: None,
             }