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

tldr/sed

@@ -0,0 +1,22 @@
+---
+syntax: markdown
+tags: [tldr, common]
+source: https://github.com/tldr-pages/tldr.git
+---
+# sed
+
+> Edit text in a scriptable manner.
+> See also: `awk`, `ed`.
+> More information: <https://manned.org/man/sed.1posix>.
+
+- Replace all `apple` (basic regex) occurrences with `mango` (basic regex) in all input lines and print the result to `stdout`:
+
+`{{command}} | sed 's/apple/mango/g'`
+
+- Execute a specific script [f]ile and print the result to `stdout`:
+
+`{{command}} | sed -f {{path/to/script.sed}}`
+
+- Print just a first line to `stdout`:
+
+`{{command}} | sed -n '1p'`