Manpages: Auto-generate many through ArgsParser

This set was hand-curated, guided by the questions:
- Does it have at least three options, i.e. is the help page
  non-trivial?
- Is the program unusual, i.e. does listing it in Help or on
  man.serenityos.org spread awareness?
- Is the program common, but we only implement a subset of 'common'
  flags?

Base/usr/share/man/man1/lsof.md

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+## Name
+
+lsof
+
+## Synopsis
+
+```sh
+$ lsof [-p pid] [-d fd] [-u login/UID] [-g PGID] [filename]
+```
+
+## Description
+
+List open files of a processes. This can mean actual files in the file system, sockets, pipes, etc.
+
+## Options:
+
+* `--help`: Display help message and exit
+* `--version`: Print version
+* `-p pid`: Select by PID
+* `-d fd`: Select by file descriptor
+* `-u login/UID`: Select by login/UID
+* `-g PGID`: Select by process group ID
+
+## Arguments:
+
+* `filename`: Filename
+
+<!-- Auto-generated through ArgsParser -->