Update whenever gem 0.8.4 -> 0.9.0

0.9.0 / December 17, 2013

  - Capistrano V3 support. [Philip Hallstrom]
  - Process params in job templates. [Austin Ziegler]

The chronic gem, which is a dependency of whenever, was also updated.

Change-Id: Iaa57e6c4776e77c6af2dfb7afb2bce4224023fe0