Add ExpressionEngine CMS autocompletion (#6556)

plugins/eecms/eecms.plugin.zsh

+# ExpressionEngine CMS basic command completion
+
+_eecms_console () {
+    echo "php $(find . -maxdepth 3 -mindepth 1 -name 'eecms' -type f | head -n 1)"
+}
+
+_eecms_get_command_list () {
+    `_eecms_console` | sed "/Available commands/,/^/d" | sed "s/[[:space:]].*//g"
+}
+
+_eecms () {
+    compadd `_eecms_get_command_list`
+}
+
+compdef _eecms '`_eecms_console`'
+compdef _eecms 'system/ee/eecms'
+compdef _eecms eecms
+
+#Alias
+alias eecms='`_eecms_console`'