Re-implemented all development Rake tasks in Thor. Now actually tested.

Fixes:
* https://www.pivotaltracker.com/story/show/25484287 & https://github.com/pivotal/jasmine/issues/183
* https://www.pivotaltracker.com/story/show/25485401 & https://github.com/pivotal/jasmine/issues/189
* https://www.pivotaltracker.com/story/show/25485953 & https://github.com/pivotal/jasmine/issues/159

spec/spec_helper.rb

@@ -0,0 +1,51 @@
+# This file was generated by the `rspec --init` command. Conventionally, all
+# specs live under a `spec` directory, which RSpec adds to the `$LOAD_PATH`.
+# Require this file using `require "spec_helper.rb"` to ensure that it is only
+# loaded once.
+#
+# See http://rubydoc.info/gems/rspec-core/RSpec/Core/Configuration
+RSpec.configure do |config|
+  config.treat_symbols_as_metadata_keys_with_true_values = true
+  config.run_all_when_everything_filtered = true
+  config.filter_run :focus
+end
+
+require 'awesome_print'
+require 'tmpdir'
+require 'nokogiri'
+
+def project_root
+  File.join(File.expand_path(File.dirname(__FILE__)), '..')
+end
+
+require "#{project_root}/tasks/jasmine_dev"
+
+def capture_output(capture = true)
+  if capture
+    output = StringIO.new
+    $stdout = output
+  end
+  yield
+  if capture
+    output.string
+  end
+ensure
+  $stdout = STDOUT
+end
+
+def reset_dir(dir)
+  FileUtils.rm_r dir if File.exists?(dir)
+  FileUtils.mkdir_p dir
+end
+
+def jasmine_version
+  version = jasmine_version_object
+
+  version_string = "#{version['major']}.#{version['minor']}.#{version['build']}"
+  version_string += ".rc#{version['release_candidate']}" if version['release_candidate']
+  version_string
+end
+
+def jasmine_version_object
+  @version_object ||= JSON.parse(File.read(File.join(JasmineDev.project_root, 'src', 'version.json')))
+end