add flow.clock/format-date
remove double-check SNAPSHOT dependency
flow 0.1.2

* fix up schema from String to Str.
* format README embedded syntax properly.
* fix render-clock and execute-alert executions.
* fix application of create-action.
* edit dow.flow reference to flow.core in docstring.
* fix missing clock-name parameter in flow.core/flow.
* put missing :min in README example configs.
* move execute-alert keyword access to let block.
* add flow.clock/format-date.
* remove double-check SNAPSHOT dependency.