zsh: add function to generate i3/sway configs

.config/zsh/functions/gen_i3sway_config

@@ -0,0 +1,11 @@
+#!/usr/bin/env zsh
+# generates config for i3 and sway by combining the common and local configs
+
+setopt LOCAL_OPTIONS ERR_RETURN NO_UNSET PIPE_FAIL
+
+for wm in i3 sway; do
+    local dir=${HOME}/.config/${wm}
+
+    [[ -f ${dir}/config.local ]] || touch ${dir}/config.local
+    \cat ${dir}/config.common ${dir}/config.local > ${dir}/config
+done