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

tldr/zdiff

@@ -0,0 +1,17 @@
+---
+syntax: markdown
+tags: [tldr, common]
+source: https://github.com/tldr-pages/tldr.git
+---
+# zdiff
+
+> Invoke `diff` on `gzip` archives.
+> More information: <https://manned.org/zdiff>.
+
+- Compare two files, uncompressing them if necessary:
+
+`zdiff {{path/to/file1.gz}} {{path/to/file2.gz}}`
+
+- Compare a file to a `gzip` archive with the same name:
+
+`zdiff {{path/to/file}}`