Enforce linebreak style (#1213)

* Now forcing Unix linebreak style.

* Added linebreak style for Solidity files.

.soliumrc.json

@@ -4,6 +4,7 @@
   "rules": {
     "error-reason": "off",
     "indentation": ["error", 2],
+    "linebreak-style": ["error", "unix"],
     "max-len": ["error", 79],
     "no-constant": ["error"],
     "no-empty-blocks": "off",