docs: fix some typos/leftovers (#1989)

Signed-off-by: Nick Yamane <nick.diego@gmail.com>

docs/90-FAQ.md

@@ -92,9 +92,9 @@ Example key binding for your `globalkeys`:
 
 If you want to execute a shell command or need to execute a command that uses
 redirection, pipes and so on, do not use the `awful.spawn` function but
-`awful.util.spawn_with_shell`. Here is an example:
+`awful.spawn.with_shell`. Here is an example:
 
-    awful.key({ modkey }, "F10", function () awful.util.spawn_with_shell("cal -m | xmessage -timeout 10 -file -") end)
+    awful.key({ modkey }, "F10", function () awful.spawn.with_shell("cal -m | xmessage -timeout 10 -file -") end)
 
 On zsh, any changes to $PATH you do in `~/.zshrc` will not be picked up (because
 this is only run for interactive shells). Use `~/.zshenv` instead to make

docs/common/widget.ldoc

@@ -1,11 +1,11 @@
 
---- Get a widex index.
+--- Get a widget index.
 -- @param widget The widget to look for
 -- @param[opt] recursive Also check sub-widgets
--- @param[opt] ... Aditional widgets to add at the end of the "path"
+-- @param[opt] ... Aditional widgets to add at the end of the path
 -- @return The index
 -- @return The parent layout
--- @return The path between "self" and "widget"
+-- @return The path between self and widget
 -- @function index
 
 --- Get all direct and indirect children widgets.

lib/awful/rules.lua

@@ -247,7 +247,7 @@ end
 -- By default, the table has the following functions:
 --
 -- * geometry
--- * switchtotag
+-- * placement
 --
 -- @tfield table awful.rules.extra_properties
 rules.extra_properties = {}
@@ -275,6 +275,9 @@ rules.high_priority_properties = {}
 --- Delayed properties.
 -- Properties applied after all other categories.
 -- @tfield table awful.rules.delayed_properties
+-- By default, the table has the following functions:
+--
+-- * switchtotag
 rules.delayed_properties = {}
 
 local force_ignore = {