Added Russian Translations

Redo of the PR #598

**Added:**
- Russian Translations

**Fixed:**
- corrected .gitignore rules for default modules

(Reasoning behind change: when I added translation for `alert` module `git add` was telling me that `.gitignore` rule excludes files and folders under `modules/default`)

I also noticed that `.gitignore:56` has following declaration:

```
!/modules/node_helper
!/modules/node_helper/**
```
but I don't think this directory structure exists today (also there is a small typo)

modules/default/alert/translations/ru.json

@@ -0,0 +1,4 @@
+{
+  "sysTitle": "MagicMirror Уведомление",
+  "welcome": "Добро пожаловать, старт был успешным!""
+}