Add a pre-commit hook configuration to check YAML and whitespace.

These are minor, but avoids those coming up during reviews at all.

Signed-off-by: Diego Elio Pettenò <flameeyes@flameeyes.com>

.pre-commit-config.yaml

@@ -11,3 +11,9 @@ repos:
     rev: latest
     hooks:
     - id: reuse
+-   repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v2.3.0
+    hooks:
+    -   id: check-yaml
+    -   id: end-of-file-fixer
+    -   id: trailing-whitespace

examples/server/static/led_color_picker_example.js

@@ -127,4 +127,3 @@ function getCursorPosition(canvas, event) {
 
 drawColorPicker();
 canvas.addEventListener('mousedown', onColorPick);
-