adds HistoryArray#to_h and spec
Remove unecessary eval's from cd_spec
Add `.cd -` to return to prior working directory

[Finishes #1028]
Merge pull request #1033 from jasonLaster/pry_tester_eval

Remove unecessary eval's from cd_spec
Merge pull request #1032 from DanielleSucher/add-cd-dash

Add `.cd -` to return to prior working directory
Only take a shallow clone
Merge branch 'to_h'
solved issue 998
issue 998
Update ShellCommand so that  autocompletes to
Merge pull request #1036 from jasonLaster/add-cd-home

Update ShellCommand so that `.cd` autocompletes to `.cd ~`
issue 998
issue 998
Remove define of Pry class attributes from lib/pry/pry_class.rb to lib/pry.rb . pry/commands and Pry.config have circular-dependency. In rare case (c.f . #978) Pry.config is initialized not properly. We will fix this bug by this commit.
issue 998 test added
method_spec.rb fixed
Simplify

By putting the check for [] first, we don't need to handle the
case where that's part of the method.
undo whitespace changes
Merge branch 'show-get'
Fix load error(forwardable), remove require 'forwardable' from pry/pry_class.rb to pry.rb