v0.3.0: Cancellation and better defaults

• Supports cancellation of in-flight execution by returning an opaque cancellation handle you can call cancel() on
• Defaults printing to stdout and stderr to false to make it easier to run background tasks silently
• Fixes implementation of tests to make them more robust

v0.2.0: Minor fixes

• Mark additional members of Process API as public that were missed in the original release
• Minor tweaks to README

v0.1.0: Initial release

Initial implementation of Coquille, supporting:

• Simple API for specifying commands and arguments
• async API for running shell commands
• Support for default printing to stdout and stderr
• Support for handlers to stream stdout and stderr from the child process to
• Basic test coverage