A start at a gem-based plugin whitelist for Pages.
Add --whitelist flag and internal logic
Remove Site.whitelist attribute.
Empty file for windows docs.
Some beginning collection for Windows users.

Leaving the office so it's a bit unkempt.
Add additional information about encoding issues on Windows
Add note about auto-regeneration
Add block of code which should be added to Gemfile for Windows listen compatibility.

Closes https://github.com/mojombo/jekyll/pull/1720
Add syntax for mercenary CLI engine by @mojombo
Fix serve -> server alias, ensure --drafts is mapped to show_drafts
Switch from commander to mercenary in gemspec
Let jekyll-import specify subcommands and their options for each importer.

@mojombo, this look better?
Check if JekyllImport is defined using Object#const_defined?
If no args are given, then list possible importers.
move self.type to convertible
Merge branch 'master' into frontmatter-defaults
Add test code for 'whitelist' option.
Remove option from CLI
Add "jekyll_test_plugin_malicious" as gem dep
The whitelist should be an array (not a file)

Default to `[]` if the key’s value is falsey