xwininfo: add page; xkill: update page (#11945)

* xwininfo: add page ant pt_BR translation

* xkill: update page and pt_BR translation

* xwininfo: update pt_BR translation

* xwininfo: fix ID casing and ellipsis

Co-authored-by: K.B.Dharun Krishna <kbdharunkrishna@gmail.com>

* xwininfo: fix ID casing in pt_BR

---------

Co-authored-by: K.B.Dharun Krishna <kbdharunkrishna@gmail.com>
Co-authored-by: Isaac Vicente <isaacvicentsocial@gmail.com>

pages/common/xkill.md

@@ -1,7 +1,7 @@
 # xkill
 
 > Kill a window interactively in a graphical session.
-> See also `kill` and `killall`.
+> See also: `kill`, `killall`.
 > More information: <https://www.x.org/releases/current/doc/man/man1/xkill.1.xhtml>.
 
 - Display a cursor to kill a window when pressing the left mouse button (press any other mouse button to cancel):
@@ -11,3 +11,7 @@
 - Display a cursor to select a window to kill by pressing any mouse button:
 
 `xkill -button any`
+
+- Kill a window with a specific id (use `xwininfo` to get info about windows):
+
+`xkill -id {{id}}`