CLI setting for custom homebridge "home" path

Fixes #378

lib/user.js

@@ -14,6 +14,9 @@ module.exports = {
 // global cached config
 var config;
 
+// optional custom storage path
+var customStoragePath;
+
 function User() {
 }
   
@@ -22,6 +25,7 @@ User.config = function() {
 }
   
 User.storagePath = function() {
+  if (customStoragePath) return customStoragePath;
   var home = process.env.HOME || process.env.HOMEPATH || process.env.USERPROFILE;
   return path.join(home, ".homebridge");
 }
@@ -33,3 +37,7 @@ User.configPath = function() {
 User.persistPath = function() {
   return path.join(User.storagePath(), "persist");
 }
+
+User.setStoragePath = function(path) {
+  customStoragePath = path;
+}