Fix capitalization handling in country download

This is a small PR into #487
that allows country codes to be specified in upper case or lower case.

Before this, specifying country codes in anything but lowercase would
cause the downloader to skip all files.

utils/download_sqlite_all.js

@@ -17,6 +17,13 @@ function on_done() {
   console.log('All done!');
 }
 
+function getCountriesToDownload() {
+  const countries = Array.isArray(config.imports.whosonfirst.countryCode) ?
+    config.imports.whosonfirst.countryCode : [config.imports.whosonfirst.countryCode];
+
+  return countries.map((c) => { return c.toLowerCase(); });
+}
+
 function download(callback) {
   //ensure required directory structure exists
   fs.ensureDirSync(path.join(config.imports.whosonfirst.datapath, 'sqlite'));
@@ -29,8 +36,7 @@ function download(callback) {
   const cpuCount = os.cpus().length;
   const simultaneousDownloads = Math.max(maxSimultaneousDownloads, Math.min(1, cpuCount / 2));
   const countryFilter = () => {
-    const countries = Array.isArray(config.imports.whosonfirst.countryCode) ?
-    config.imports.whosonfirst.countryCode : [config.imports.whosonfirst.countryCode];
+    const countries = getCountriesToDownload();
     return (e) => {
       if (countries.length === 0) {
         // This is specific to geocode earth, it will select global sqlites
@@ -108,4 +114,4 @@ function download(callback) {
   async.parallelLimit(downloadFunctions, simultaneousDownloads, callback);
 }
 
-download(on_done);
+download(on_done);