ls, stty: Remove platform-specific pages (#4620)

tldr pages for `command` and `stty` in specific platforms are identical
to their counterparts in the common folder.

pages/osx/command.md

@@ -1,7 +0,0 @@
-# command
-
-> Command forces the shell to execute the program and ignore any functions, builtins and aliases with the same name.
-
-- Execute the ls program literally, even if an ls alias exists:
-
-`command {{ls}}`

pages/osx/stty.md

@@ -1,23 +0,0 @@
-# stty
-
-> Set options for a terminal device interface.
-
-- Display all settings for the current terminal:
-
-`stty -a`
-
-- Set the number of rows:
-
-`stty rows {{rows}}`
-
-- Set the number of columns:
-
-`stty cols {{cols}}`
-
-- Get the actual transfer speed of a device:
-
-`stty -f {{path/to/device_file}} speed`
-
-- Reset all modes to reasonable values for the current terminal:
-
-`stty sane`

pages/sunos/stty.md

@@ -1,23 +0,0 @@
-# stty
-
-> Set options for a terminal device interface.
-
-- Display all settings for the current terminal:
-
-`stty -a`
-
-- Set the number of rows:
-
-`stty rows {{rows}}`
-
-- Set the number of columns:
-
-`stty cols {{cols}}`
-
-- Get the actual transfer speed of a device:
-
-`stty -f {{path/to/device_file}} speed`
-
-- Reset all modes to reasonable values for the current terminal:
-
-`stty sane`