update readme and bump version

Author: devigned

README.md

@@ -90,7 +90,7 @@ you can ```vagrant up``` and use ```azure``` provider. For example:
 
 ```sh
 $ vagrant box add azure https://github.com/azure/vagrant-azure/raw/v2.0/dummy.box --provider azure
-$ vagrant plugin install vagrant-azure --plugin-version '2.0.0.pre8'
+$ vagrant plugin install vagrant-azure
 $ vagrant up --provider=azure
 ```
 

lib/vagrant-azure/version.rb

@@ -4,6 +4,6 @@
 
 module VagrantPlugins
   module Azure
-    VERSION = '2.0.0.pre8'.freeze
+    VERSION = '2.0.0'.freeze
   end
 end