Rename `get_binding` to `get_keyboard_binding` and ensure that this
function only accesses bindings of type B_KEYBOARD. Other types of
bindings (e.g. mouse bindings) will be accessed by a different function.
The implementation is naive because the user has to generate exactly the
event he specified. That is, if you use this binding:
bindsym --release $mod+x exec import /tmp/latest-screenshot.png
Then it will only be triggered if you hit $mod, hit x, release x,
release $mod. It will not be triggered if you hit $mod, hit x, release
$mod, release x. The reason is that the KeyRelease event in the latter
case will not have the modifier in its flags, so it doesn’t match the
configured binding.
e.g. pressing Mod1+x when having the following in your configfile:
bindsym Mod1+x some invalid command
will lead to an i3-nagbar instance popping up, offering you to view the
error log (which will contain parser errors from this commit on).
