Add pre-commit hook (HunterMcGushion#78)

* chore(): added pre-commit hook

Co-authored-by: Bjorn Heesakkers <bjorn.heesakkers@sendcloud.com>
Co-authored-by: Michael <code@mweiss.ch>

Author: bjornconstructors

.pre-commit-hooks.yaml

@@ -0,0 +1,9 @@
+- id: docstr-coverage
+  name: docstr-coverage
+  entry: docstr-coverage
+  require_serial: true
+  language: python
+  language_version: python3
+  types_or: [cython, pyi, python]
+  minimum_pre_commit_version: "2.9.0"
+  always_run: true

README.md

@@ -170,6 +170,21 @@ class FooBarChild(FooBar):
         pass
 ```
 
+#### Pre-commit hook
+
+You can use `docstr-coverage` as a pre-commit hook by adding the following to your `.pre-commit-config.yaml` file:
+
+To pass arguments to `docstr-coverage`, add a `.docstr.yaml` config (which is automatically picked up).
+ This is preferrable over [pre-commit args](https://pre-commit.com/#config-args), 
+ as it facilitates the use of the same config in ci / pre-commit and manual runs.
+
+```yaml
+- repo: https://github.com/HunterMcGushion/docstr_coverage
+  rev: <most recent docstr-coverage release or commit sha>
+  hooks:
+    - id: docstr-coverage
+```
+
 #### Package in Your Project
 
 You can also use `docstr-coverage` as a part of your project by importing it thusly.