Add route to set/get sysinfo

src/sysinfo.js

@@ -2,6 +2,7 @@
 
 exports = module.exports = {
     getServerIp: getServerIp,
+    testConfig: testConfig,
 
     hasIPv6: hasIPv6
 };
@@ -41,3 +42,10 @@ function hasIPv6() {
     // on contabo, /proc/net/if_inet6 is an empty file. so just exists is not enough
     return fs.existsSync(IPV6_PROC_FILE) && fs.readFileSync(IPV6_PROC_FILE, 'utf8').trim().length !== 0;
 }
+
+function testConfig(config, callback) {
+    assert.strictEqual(typeof config, 'object');
+    assert.strictEqual(typeof callback, 'function');
+
+    api(config.provider).testConfig(config, callback);
+}