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

tldr/pgrep

@@ -0,0 +1,21 @@
+---
+syntax: markdown
+tags: [tldr, common]
+source: https://github.com/tldr-pages/tldr.git
+---
+# pgrep
+
+> Find or signal processes by name.
+> More information: <https://www.man7.org/linux/man-pages/man1/pkill.1.html>.
+
+- Return PIDs of any running processes with a matching command string:
+
+`pgrep {{process_name}}`
+
+- Search for processes including their command-line options:
+
+`pgrep --full "{{process_name}} {{parameter}}"`
+
+- Search for processes run by a specific user:
+
+`pgrep --euid root {{process_name}}`