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

tldr/docker-diff

@@ -0,0 +1,17 @@
+---
+syntax: markdown
+tags: [tldr, common]
+source: https://github.com/tldr-pages/tldr.git
+---
+# docker diff
+
+> Inspect changes to files or directories on a container's filesystem.
+> More information: <https://docs.docker.com/engine/reference/commandline/diff>.
+
+- Inspect the changes to a container since it was created:
+
+`docker diff {{container}}`
+
+- Display help:
+
+`docker diff --help`