Merge: Allow controllers to set PDFKit-save-pdf

Conflicts:
	lib/pdfkit/middleware.rb
Merge: get first PDFKit-save-pdf test passing

Conflicts:
	lib/pdfkit/middleware.rb
Merge: PDFKit-save-pdf pdf save header tests

Conflicts:
	lib/pdfkit/middleware.rb
prevent header corruption in tests
Fix up gemspec
Add .ruby-version, .ruby-gemset

Fixes #202
update README.md for PDFKit-save-pdf.
Escape \X in stylesheets
Merge pull request #204 from maxd/master

Escape \X in stylesheets
Show wkhtmltopdf exit status on errors
Treat status code 2 as success
Format commands and file paths
Merge pull request #210 from rafalchmiel/patch-1

Format commands and file paths
Merge pull request #209 from sealink/allow-missing-assets

Allow missing assets
:panda_face: Fixed bug to not add root url for protocl relative urls.
Merge pull request #212 from miry/translate_path_bug

Fixed bug to not add root url for protocl relative urls.
Allow to use repeatable options example like --cookie via meta tags.
An attempt at allow hashes for repeatable options
Document where the repeatable options came from

[ci skip]
Use arrays for hash keys