Export Parser types

- Move the Parser namespace into the Bowser namespace
- Make the Parser class an interface so consumers can't construct a Parser class (this is not exported by bowser)

index.d.ts

@@ -6,7 +6,6 @@ export = Bowser;
 export as namespace Bowser;
 
 declare namespace Bowser {
-
   /**
    * Creates a Parser instance
    * @param {string} UA - User agent string
@@ -22,11 +21,10 @@ declare namespace Bowser {
    */
 
   function parse(UA: string): Parser.ParsedResult;
-}
 
-declare namespace Parser {
-	class Parser {
-		constructor(UA: string, skipParsing?: boolean);
+  namespace Parser {
+    interface Parser {
+      constructor(UA: string, skipParsing?: boolean): Parser.Parser;
 
       /**
        * Get parsed browser object
@@ -222,3 +220,4 @@ declare namespace Parser {
       [key: string]: any;
     }
   }
+}