Track installed gem version and display in startup logger information

lib/vagrant.rb

@@ -248,7 +248,7 @@ plugins = Vagrant::Plugin::Manager.instance.installed_plugins
 
 global_logger.info("Plugins:")
 plugins.each do |plugin_name, plugin_info|
-  global_logger.info("  - #{plugin_name} = #{plugin_info[:version]}")
+  global_logger.info("  - #{plugin_name} = #{plugin_info["installed_gem_version"]}")
 end
 
 if Vagrant.plugins_init?

lib/vagrant/plugin/manager.rb

@@ -78,6 +78,7 @@ module Vagrant
           version: opts[:version],
           require: opts[:require],
           sources: opts[:sources],
+          installed_gem_version: result.version
         )
 
         result