New unity component can be used for testing other applications.
Upstream version of Unity is included as a submodule.
Utilities specific to ESP-IDF unit tests (partitions, leak checking
setup/teardown functions, etc) are kept only in unit-test-app.
Kconfig options are added to allow disabling certain Unity features.
This commit updates various test cases throughout esp-idf such that
the values used for timer divider pass the assertions in the timer component.
Timer divider values must be between 2 to 65536
Previously if multiple tasks had been added to xPendingReadyList for the CPU, only the first one was resumed.
Includes a test case for resuming multiple (pending) tasks on xTaskResumeAll().
Document the limitation that while scheduler is suspended on one CPU, it can't wake tasks on either CPU.
