targets 0.3.0

Bug fixes

Fix the "write target at cursor" RStudio addin and move cursor between the parentheses.

Add a backoff option in tar_option_set() to set the maximum upper bound (seconds) for the polling interval (#333).
Add a new tar_github_actions() function to write a GitHub Actions workflow file for continuous deployment of data analysis pipelines (#339, @jaredlander).
Add a new TAR_MAKE_REPORTER environment variable to globally set the reporter of the tar_make*() functions (#345, @alexpghayes).
Support new storage formats "feather", "parquet", "aws_feather", and "aws_parquet" (#355, @riazarbi).

Implement an exponential backoff algorithm for polling the priority queue in tar_make_clustermq() and tar_make_future() (#333).
In tar_make_future(), try to submit a target every time a worker is polled.
In tar_make_future(), poll workers in order of target priority.
Avoid the time delay in exiting on error (from r-lib/callr#185).
Clone target objects for the pipeline and scrape more targets internal objects out of the environment in order to avoid accidental massive data transfers to workers.

Use rlang::check_installed() inside assert_package() (#331, @malcolmbarrett).
Allow tar_destroy(destroy = "process").
In tar_watch(), increase default seconds to 15 (previously 5).
In tar_watch(), debounce instead of throttle inputs.
In tar_watch(), add an action button to refresh the outputs.
Always deduplicate metadata after tar_make(). Will help compute a cache key on GitHub Actions and similar services.
Deprecate tar_deduplicate() due to the item above.
Reorder information in timestamped messages.
Document RNG seed generation in tar_target_raw(), tar_meta(), and tar_seed() (#357, @alexpghayes).
Switch meaning of %||% and %|||% to conform to historical precedent.
Only show a command line spinner if reporter = "silent" (#364, @matthiasgomolka).
Target and pipeline objects no longer have an envir element.