Bulk conversion to expect syntax

I used transpec to do a bulk upgrade the specs which are (semi-) automatically updateable. I tried to put only similar changes into one commit that is easy to see them in a split diff. Except from b8382ec every commit should be "green".

I read the "taking it slow" part from #1294 perfectly timed after I finished this, so feel free to cherry-pick the non-transtec commits if that fits better into the upgrade plan ;)

This is way not enough to disable the should syntax (many files are untouched at all), but I think it is good have them converted to get a better overview of the 'real' work:

    Converting spec/command_spec.rb
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/command_spec.rb:235:          args.should == ['four']
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/command_spec.rb:236:          opts[:f].should == 4
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/command_spec.rb:260:          opts.fetch_command(:blahblah).should == nil
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/command_spec.rb:261:          opts.fetch_command(:yell).present?.should == true
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/command_spec.rb:277:          args.should == ['papa']
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/command_spec.rb:278:          opts.fetch_command(:yell).present?.should == true
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/command_spec.rb:279:          opts.fetch_command(:yell).person?.should == true
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/command_spec.rb:293:          args.should == ['yell', 'papa', 'sonny', 'daughter']
    Converting spec/commands/cd_spec.rb
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/commands/cd_spec.rb:12:        binding_stack.map { |b| b.eval('self') }.should == other
    Converting spec/commands/edit_spec.rb
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/commands/edit_spec.rb:563:            X.method(:x).owner.should == self
    Converting spec/commands/show_doc_spec.rb
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/commands/show_doc_spec.rb:36:      pry_eval(binding, 'show-doc').should =~ /sample comment/
    Converting spec/commands/show_source_spec.rb
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/commands/show_source_spec.rb:36:      pry_eval(binding, 'show-source').should =~ /def @o.sample/
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/commands/show_source_spec.rb:43:      pry_eval(binding, 'show-source -l').should =~ /def @o.sample/
    Converting spec/commands/whereami_spec.rb
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/commands/whereami_spec.rb:23:        pry_eval(binding, 'whereami').should =~ /Cor[#]blimey!/
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/commands/whereami_spec.rb:36:          should == File.expand_path(__FILE__)
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/commands/whereami_spec.rb:110:          pry_eval(binding, 'whereami 3').should =~ /class Cor/
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/commands/whereami_spec.rb:124:          pry_eval(binding, 'whereami -m').should =~ /def blimey/
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/commands/whereami_spec.rb:137:          pry_eval(binding, 'whereami -f').should =~ /show entire file when -f option used/
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/commands/whereami_spec.rb:152:            out.should =~ /class Cor/
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/commands/whereami_spec.rb:153:            out.should =~ /blimey/
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/commands/whereami_spec.rb:166:            out.should =~ /class Cor/
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/commands/whereami_spec.rb:167:            out.should =~ /blimey/
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/commands/whereami_spec.rb:187:            out.should =~ /class Cor/
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/commands/whereami_spec.rb:188:            out.should =~ /blimey/
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/commands/whereami_spec.rb:199:        out.should =~ /^\s*def/
    Cannot convert #should_not into #expect since #expect is not available in the context.
    spec/commands/whereami_spec.rb:200:        out.should_not =~ /\=\>/
    Converting spec/pry_spec.rb
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/pry_spec.rb:12:        input('BasicObject.new').should =~ /^=> #<BasicObject:/
    Converting spec/spec_helpers/repl_tester.rb
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/spec_helpers/repl_tester.rb:75:    match.should === last_prompt
    Cannot convert #should into #expect since #expect is not available in the context.
    spec/spec_helpers/repl_tester.rb:81:    match.should === @pry.output.string.chomp