fix all hints of shellcheck.net linter

create-geojson.sh

@@ -1,8 +1,11 @@
 #!/usr/bin/env sh
 echo "this takes some time depending on the amount of addresses in your lists …"
-for file in $(ls *-csv) ; do
-	out=$(echo ${file}|cut -d- -f1)".geojson"
-	test -e ${out} && { echo "file exists: "${out}", skipping."; continue; }
-	echo ./lookup.py ${file}
-	./lookup.py ${file} 2>/dev/null > ${out}
+for file in *-csv ; do
+	out=$(echo "${file}"|cut -d- -f1)".geojson"
+	if test -e "${out}" ; do
+		echo "file exists: ${out}, skipping."
+		continue
+	fi
+	echo ./lookup.py "${file}"
+	./lookup.py "${file}" 2>/dev/null > "${out}"
 done