Manage passphrase of gpg key used for RPM signing.
How to build and sign RPMs.
Note that package_scripts_path is also used for RPMs.
Mention that the omnibus cookbook installs packaging dependencies.
Merge pull request #290 from opscode/yzl/manage-rpmbuild-passphrase

Manage passphrase for rpm signing
Use a consistent method for rendering ERB files
Deprecate Config.package_tmp (use tmpdir instead)
Expand package_dir relative to project_root
Ensure the staging_dir is removed at the end of the build
Include Digestable in Packager::Base
Add DEB packager
Follow the same patterns in RPM as DEB
Packagers should create the package_dir
Document Project#log_key
Rename DSL method replaces -> replace and make replaces a public API method
Default package_user to "root" if nothing is specified
Default package to "Ohai['root_group']" if nothing is specified
Remove fpm
Use Omnibus.logger in Config
Include Logging module in Templating