Adding Softmax Player

The softmax algorithm is an alternative to the epsilon-greedy algorithm.
Instead of picking based on a set probability, it uses a 'temperature'
parameter, along with the known data to set the distribution of the
alternatives.

lib/bandit.rb requires the softmax player
lib/bandit/players/base.rb adds a softmax option to the factory
lib/bandit/players/softmax.rb implements the player
players.rdoc provides a short explanation
Adding Rake test_player task

Usage: rake bandit:test_player[<test_name>{,<true|false>}]

The test_player task is called with one mandatory argument, the name of
an experiment, and one optional parameter, a boolean determing whether
or not to force.  The configured player for the given environment is the
player that is tested.

Force is only required if running the test in a non-development,
non-test environment.

The purpose of the task to to check if conversion_rates line up nicely
with the player's options.  It can be used to check the accuracy of
players, or to learn what kind of results they produce.
Adhering to Rails 3.1+ asset pipeline structure

By default, the asset pipeline looks in [app|lib|vendor]/assets/ for public assets, not the root of [app|lib|vendor].