Version 3.2.1

• Add optional pre_hook_with_context method to the Command base class,
  which takes a single parameter called context. The value of that parameter
  is provided by the caller of AccountRunner.run. In the case of the awsrun
  CLI commands, that context is an instance of awsrun.cli.Context, which
  provides command authors access to the account loader and session provider
  plug-ins as well as the full list of accounts being processed. For example,
  this would allow you to write a command that performs a VPC peering. While
  processing the account from which the peering is initiated, you can now
  obtain credentials for the other account to accept the request by using the
  session provider.

• Update the license to Apache 2.0.