安装配置dradis

github：https://github.com/dradis/dradis-ce/blob/master/README.md

安装出现错误：
== Copying sample files ==

== Preparing database ==
/usr/lib/ruby/vendor_ruby/bundler/resolver.rb::in `block in initialize': undefined method `add_root_vertex' for Molinillo::DependencyGraph:[]:Molinillo::DependencyGraph (NoMethodError)
    from /usr/lib/ruby/vendor_ruby/bundler/resolver.rb::in `initialize'
    from /usr/lib/ruby/vendor_ruby/bundler/resolver.rb::in `new'
    from /usr/lib/ruby/vendor_ruby/bundler/resolver.rb::in `resolve'
    from /usr/lib/ruby/vendor_ruby/bundler/definition.rb::in `resolve'
    from /usr/lib/ruby/vendor_ruby/bundler/definition.rb::in `specs'
    from /usr/lib/ruby/vendor_ruby/bundler/definition.rb::in `specs_for'
    from /usr/lib/ruby/vendor_ruby/bundler/definition.rb::in `requested_specs'
    from /usr/lib/ruby/vendor_ruby/bundler/environment.rb::in `requested_specs'
    from /usr/lib/ruby/vendor_ruby/bundler/runtime.rb::in `setup'
    from /usr/lib/ruby/vendor_ruby/bundler.rb::in `setup'
    from /usr/lib/ruby/vendor_ruby/bundler/setup.rb::in `<top (required)>'
    from /usr/lib/ruby/2.2./rubygems/core_ext/kernel_require.rb::in `require'
    from /usr/lib/ruby/2.2./rubygems/core_ext/kernel_require.rb::in `require'
    from /var/lib/dradis-ce/config/boot.rb::in `<top (required)>'
    from bin/rake::in `require_relative'
    from bin/rake::in `<main>'

== Removing old logs and tempfiles ==

解决方法：

$ apt-get install libsqlite3-dev
$ apt-get install mysql-server mysql-client libmysqlclient-dev
$ apt-get install redis-server
$ redis-server
$ apt-get update
$ apt-get install --only-upgrade bundler
$ redis-cli ping

　　Expected output:

　　PONG