Language

Operator < now works on arrays and performs lexicographic comparison.
New stdlib functions std.objectValues and std.objectValuesAll for getting an array on field values.
Bitshift by negative value is now an error (previously the behavior was inconsistent).

Go implementation

New tool available: jsonnet-lint which automatically finds common problems in Jsonnet programs.
New tool available: jsonnet-deps which finds all transitive dependencies.
Fixed multiple issues with stack traces, which sometimes resulted in missing or confusing stack trace entries.
Fixed handling of object locals in object comprehensions.
Added missing convenience functions to C and Python bindings. They should be now 100% complete.
Python bindings no longer hold GIL during evaluation of Jsonnet code.
std.manifestJsonEx is now much faster.
Strings are now supported in std.flatMap (in addition to arrays).
Improved Go library API: more consitent handling of paths. We no longer treat fake names for ad hoc snippets or extvars as paths. Function family EvaluateSnippet* is now deprecated in favor of EvaluateAnonymousSnippet* or EvaluateFile*.
When using bazel, it is possible now to use go_repository rule for go-jsonnet.

The shared test suite allows specifying an overriding directory for test results (useful for error messages).
Added a mechanism to C++ interpreter to call normal Jsonnet functions in the implementation of builtin operations (currently it's used for implementing array comparison).
The tests.sh script for go-jsonnet no longer refreshes cpp-jsonnet submodule.
Added a separate script for updating cpp-jsonnet, which automatically regenerates stdlib.