Allow to create a self-signed cert on Ruby 1.8

Base64.urlsafe_encode64 is only available on Ruby 1.9.
If we are on Ruby 1.8, we provide an equivalent implementation
on our own.
Add not_before and not_after to the data bag.

This could make it easier to search for certs nearing their end-of-life.
Merge the ca-cert to the cert

Add the ca-certificate to the cert to get at least a start of an cachain.
Switching to secure rubygems.org source

When running bundle on the client-gem Gemfile, a deprecation warning was
being shown.

  The source :rubygems is deprecated because HTTP requests are insecure.
  Please change your source to 'https://rubygems.org' if possible, or
  'http://rubygems.org' if not.

Switching the source line fixes that warning.
Merge remote-tracking branch 'dougbarth/fix_rubygems_source'

* dougbarth/fix_rubygems_source:
  Switching to secure rubygems.org source
Merge remote-tracking branch 'kampfschlaefer/create_cachain'

* kampfschlaefer/create_cachain:
  Merge the ca-cert to the cert
Merge remote-tracking branch 'kampfschlaefer/add_not_after'

* kampfschlaefer/add_not_after:
  Add not_before and not_after to the data bag.
Merge remote-tracking branch 'rtkmhart/master'

* rtkmhart/master:
  Fix to prevent chef-ssl from crashing on bad data.
Update specs for not-after/not-before change.

We now populate the certificate's not-before and not-after dates into
the corresponding data bag, this change updates the mock to suit.
Update Gemfile.lock for change to https://rubygems.org.
Update spec for creating a CA, longer passphrase is required.

More recent OpenSSLs are enforcing a longer passphrase length
requirement.
Merge remote-tracking branch 'meineerde/fix/ruby18-compatibility'

* meineerde/fix/ruby18-compatibility:
  Allow to create a self-signed cert on Ruby 1.8
Update cookbook's Gemfile.lock for secure Rubygems source.
Version 1.1.0