Move pages under tldr, lint run.sh, update docs

tldr/linux/light

@@ -0,0 +1,25 @@
+---
+syntax: markdown
+tags: [tldr, linux]
+source: https://github.com/tldr-pages/tldr.git
+---
+# light
+
+> Control the backlight of your screen.
+> More information: <https://manned.org/light>.
+
+- Get the current backlight value in percent:
+
+`light`
+
+- Set the backlight value to 50 percent:
+
+`light -S {{50}}`
+
+- Reduce 20 percent from the current backlight value:
+
+`light -U {{20}}`
+
+- Add 20 percent to the current backlight value:
+
+`light -A {{20}}`