Update snakeCase.js

hello; it will be a great honor to contribute in this exercise solution;
1. I think it is better to replace the "-" with a space "  " in the beginning because that will create some mistakes when  - come with an uppercase letter "-A" .

2. replace the "__" by "_" at the end because if ".." come with "-"  or with uppercase will create two underscores.
              
I hope this helps , thank you .

snakeCase/snakeCase.js

@@ -1,6 +1,6 @@
 const snakeCase = function(string) {
   // wtf case
-  string = string.replace(/\.\./g, " ");
+  string= string.replace(/[(\.\.)-]/g, " ");
 
   // this splits up camelcase IF there are no spaces in the word
   if (string.indexOf(" ") < 0) {
@@ -13,7 +13,8 @@ const snakeCase = function(string) {
     .replace(/[,\?\.]/g, "")
     .replace(/\-/g, " ")
     .split(" ")
-    .join("_");
+    .join("_")
+    .replace(/(__)/g,'_');
 };
 
 module.exports = snakeCase;