Not compatible with Redmine 2.5

[ylemarie]

Environment:

  Redmine version                2.5.1.stable
  Ruby version                   1.9.3-p194 (2012-04-20) [i486-linux]
  Rails version                  3.2.17

Started GET "/settings/plugin/redmine_better_gantt_chart" for *******
Processing by SettingsController#plugin as HTML
  Parameters: {"id"=>"redmine_better_gantt_chart"}
  Current user: ****** (id=18)
  Rendered settings/plugin.html.erb within layouts/admin (4.4ms)
Missing template, responding with 404
  Rendered common/error.html.erb within layouts/base (0.1ms)
  Rendered inline template (0.5ms)
  Rendered inline template (0.4ms)
Completed 404 Not Found in 99.0ms (Views: 84.0ms | ActiveRecord: 7.0ms)