Add {{ | jsonify }} support for hashes.
Add tests.

Need to fix up the assertions to match the output.
Fix up the assertions.
Merge pull request #3063 from jekyll/jsonify-on-hashes
Update history to reflect merge of #3063 [ci skip]
Require gems in :jekyll_plugins group in a Gemfile in unsafe mode.

Replaces #1658. /cc @imathis
Reorganize tests for plugins.
Fix 2 syntax errors.
Require plugins from Gemfile :jekyll_plugins group.
Finish up the plugin manager

And so it shall be.
Add 'b' and 's' aliases for build and serve, respectively
Merge pull request #3065 from cllns/master
Update history to reflect merge of #3065 [ci skip]
Test JEKYLL_NO_BUNDLER_REQUIRE.
Documentation for Bundler group.
Merge pull request #2865 from jekyll/some-kind-of-bundler-thingy
Update history to reflect merge of #2865 [ci skip]