Added k4a_image_get/set_system_timestamp_nsec

[wes-b]

Fixes #198

Description of the changes:

• Added k4a_image_get_system_timestamp_nsec() & k4a_image_set_system_timestamp_nsec().
• Added k4a_image_get_device_timestamp_usec().
• Added k4a_image_set_exposure_usec().
• Deprecated k4a_image_get_timestamp_usec() & k4a_image_set_timestamp_usec().
• Deprecated k4a_image_set_exposure_time_usec().
• System Timestamp on Windows is based on QueryPerformanceCounter, while Linux is based on clock_gettime(CLOCK_MONOTONIC). There is a nice writeup here: ros2/rcutils#43.
• libuvc needed to be updated to capture the time at the completion of last USB packet. So libuvc was converted from a patch to a fork.

Before submitting a Pull Request:

• I reviewed CONTRIBUTING.md
• I built my changes locally
• I ran the unit tests
• I ran the functional tests with a device
• I ran the performance tests with a device

I tested changes on:

• Windows
• Linux

[williampMSFT]

                                                   k4a_imu_sample_t *imu_sample,

This may be out of scope for this change, but figured I'd mention it:
k4a_imu_sample_t has (presumably device) timestamps embedded in it - do we need to provide a facility for getting system timestamps for IMU samples?

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Refers to: include/k4a/k4a.h:255 in ac64c8d. [](commit_id = ac64c8d, deletion_comment = False)

[schultetwin1]

Looks good! Just have 1 comment about a change to the MIN macro.

[schultetwin1]

Due to contributiuon policies, changing this to request changes since I would like MIN changed.

[wes-b]

__typeof__ is not C, I got lucky building before because that macro was never used in C code. I am reverting the change.

[schultetwin1]

__typeof__ is not C, I got lucky building before because that macro was never used in C code. I am reverting the change.

Ugh, its a GNU extension. Good find. If we are never using these MIN and MAX macros in C code, then should we include them? C++ provides a much safer std::max and std::min that we can use.

[schultetwin1]

__typeof__ is not C, I got lucky building before because that macro was never used in C code. I am reverting the change.

Ugh, its a GNU extension. Good find. If we are never using these MIN and MAX macros in C code, then should we include them? C++ provides a much safer std::max and std::min that we can use.

Talked with Wes offline, we are using these macros in C code. Looks good to me!