Release 0.4.2 (2016-11-30)

Baseline: 9e94864

Cherry picks: - 4c67807: Improve reliability/performance of Bazel downloads - ed7ced0: Support multiple mirror URLs for external repos

Incompatible changes:

Callback functions in Skylark no longer support the cfg parameter. This is a cleanup and only affects the signatures of callbacks, since the parameter hasn't been set since September 2016.

Important changes:

Prevent spurious recompiles, e.g. with changing --test_arg.
proto_library now produces a descriptor set, when built on the command-line.
Add ctx.coverage_instrumented function to Skylark, to indicate whether a specific targets should be instrumented for code coverage data collection.
Use --loading_phase_threads to control the number of threads used during the loading/analysis phase.
Structs in Skylark are tested for structural equality instead of reference equality.
Skylark implementations of http_archive, new_http_archive, and http_file.
Labels like "@foo//:foo" can now be written as "@foo" in build files
Alias proto_library's produce a descriptor set that contains all srcs of its dependencies.
External downloads now retry with exponential backoff and support gzip content-encoding.
proto_library supports strict proto deps.
A urls attribute has been added to repository rules to support multiple mirror URLs for reliably downloading files.
Top level @androidsdk support library targets have been replaced by @androidsdk//:- for Android SDK Support and Google Play Services libraries.

Build informations

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