Update jeweler for next release

[tessie]

I was trying to update the gem and then noticed that rake version etc was giving error

`NoMethodError: undefined method `dependencies_for' for #<Bundler::Runtime:0x007fcc140f96e0>
Did you mean?  dependencies
/Users/tessy/.rvm/gems/ruby-2.4.1/gems/jeweler-2.1.1/lib/jeweler/specification.rb:73:in `block in set_jeweler_defaults'
/Users/tessy/.rvm/gems/ruby-2.4.1/gems/jeweler-2.1.1/lib/jeweler/specification.rb:41:in `chdir'
/Users/tessy/.rvm/gems/ruby-2.4.1/gems/jeweler-2.1.1/lib/jeweler/specification.rb:41:in `set_jeweler_defaults'
/Users/tessy/.rvm/gems/ruby-2.4.1/gems/jeweler-2.1.1/lib/jeweler.rb:37:in `initialize'
/Users/tessy/.rvm/gems/ruby-2.4.1/gems/jeweler-2.1.1/lib/jeweler/tasks.rb:52:in `new'
/Users/tessy/.rvm/gems/ruby-2.4.1/gems/jeweler-2.1.1/lib/jeweler/tasks.rb:52:in `jeweler'
/Users/tessy/.rvm/gems/ruby-2.4.1/gems/jeweler-2.1.1/lib/jeweler/tasks.rb:82:in `block in define'
/Users/tessy/.rvm/gems/ruby-2.4.1/gems/rake-12.1.0/exe/rake:27:in `<top (required)>'
/Users/tessy/.rvm/gems/ruby-2.4.1/bin/ruby_executable_hooks:15:in `eval'
/Users/tessy/.rvm/gems/ruby-2.4.1/bin/ruby_executable_hooks:15:in `<main>'`

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