Added Pry::CLI class for processing command line options, with plugin support.

Plugins can define their own command line options by having a lib/plugin_name/cli.rb file. If this file exists
it is loaded immediately before command line options are processed. The contents of the file should be along the lines of:

Pry::CLI.add_options do
  on "my-option", "My first option!" do
    puts "I just defined an option!"
  end
end

1 files changed, 2 insertions, 80 deletions

diff --git a/bin/pry b/bin/pry
index 43863957..cd06ba94 100755
--- a/bin/pry
+++ b/bin/pry
@@ -12,83 +12,5 @@ rescue LoadError
   require 'pry'
 end
 
-opts = Slop.parse(:help => true, :multiple_switches => false) do
-  banner %{Usage: pry [OPTIONS]
-Start a Pry session.
-See: `https://github.com/pry` for more information.
-Copyright (c) 2011 John Mair (banisterfiend)
---
-}
-
-  on :e, :exec, "A line of code to execute in context before the session starts", true
-
-  on "no-pager", "Disable pager for long output" do
-    Pry.config.pager = false
-  end
-
-  on "no-history", "Disable history loading" do
-    Pry.config.history.should_load = false
-  end
-
-  on "no-color", "Disable syntax highlighting for session" do
-    Pry.color = false
-  end
-
-  on :f, "Suppress loading of ~/.pryrc" do
-    # load ~/.pryrc, if not suppressed with -f option
-    Pry.config.should_load_rc = false
-  end
-
-  on "no-plugins", "Suppress loading of plugins." do
-    # suppress plugins if given --no-plugins optino
-    Pry.config.plugins.enabled = false
-  end
-
-  on "installed-plugins", "List installed plugins." do
-    puts "Installed Plugins:"
-    puts "--"
-    Pry.locate_plugins.each do |plugin|
-      puts "#{plugin.name}".ljust(18) + plugin.spec.summary
-    end
-    exit
-  end
-
-  on "simple-prompt", "Enable simple prompt mode" do
-    Pry.prompt = Pry::SIMPLE_PROMPT
-  end
-
-  on :r, :require, "`require` a Ruby script at startup", true do |file|
-    Pry.config.requires << file
-  end
-
-  on :I, "Add a path to the $LOAD_PATH", true do |path|
-    $LOAD_PATH << path
-  end
-
-  on :v, :version, "Display the Pry version" do
-    puts "Pry version #{Pry::VERSION} on Ruby #{RUBY_VERSION}"
-    exit
-  end
-
-  on(:c, :context,
-    "Start the session in the specified context. Equivalent to `context.pry` in a session.",
-    true,
-    :default => "TOPLEVEL_BINDING"
-    )
-end
-
-# invoked via cli
-Pry.cli = true
-
-# create the actual context
-context = Pry.binding_for(eval(opts[:context]))
-
-if opts[:exec]
-  exec_string = opts[:exec] + "\n"
-else
-  exec_string = ""
-end
-
-# Start the session (running any code passed with -e, if there is any)
-Pry.start(context, :input => StringIO.new(exec_string))
-
+# Process command line options and run Pry
+Pry::CLI.run