Kotlin rules for Bazel - Legacy Rules 1.4.0

Note: These rules are maintained externally from Google (with Google's oversight and help)

Housekeeping release. Improvements to the underlying infrastructure of the rules to improve performance and correctness.

Notable changes:

Releases are now precompiled, suggested production installation is via a release archive. Please see the Development Guide when running from a non-archive repository. (#271)
Support for Kotlin compiler plugins via the kt_compiler_plugin (#308)
Improved determinism for remote builds (#304)
No longer packages non-kotlin generated sources (#263)
Proper classpath handling for java plugins (#318)
Support for propagating Kotlin version to Intellij (#242 )
Fixes to release artifact production (#326, #327)
Restructure the worker to be deterministic (cc039db, 3f4698a)
Minor cleanups (dc7fd1a)
Fix release packaging to exclude references to non-release targets. (19658cd)

Note: Some fixes on release branch have not yet been integrated into master, and so have only commits, not pull requests.

More detail can be found in the Changelog

Usage instructions can be found in the readme README

This release includes the contributions of various Googlers as well as @cgruber, @justhecuke, @szinn, @rockwotj, @IljaKroonen, @benjaminRomano, @factuno-db, @arturdryomov, @restingbull.