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This release removes the previous approach of using `fetch` and `refetch`.Instead, the user would call `execute()` on the operation handler.It is important to note that every time you call `set_variables` on the operation handler,the network layers will ignore the previous execution.If a user wants to refetch the operation, and the variables haven't changed.They can call `execute(true)` again. This will force the network layers to refetch the operation. Bug Fixes:- Bad HTTP responses will now call the `on_error` callback and can be handled nythe operation handler just as if it was an operation error. Previously, failed HTTP responseswould cause the operation handler to be in a stale state, and it couldn't be used again.- errors were not piped down to qml proxy handler. Now they are.
Contributed by [ניר](https://github.com/nrbnlulu) via [PR #477](https://github.com/qtgql/qtgql/pull/477/)