This commit makes the ur_client_library compile on windows (with MSVC). This does not mark full Windows support and should be considered an experimental addition. It was tested that everything compiles fine using MSVC and that all examples work as expected. 

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Co-authored-by: Felix Exner <feex@universal-robots.com>

This was read in the reverse order from the script. The order used in
the buffer follows the strategy that for splines it is possible to use
velocities while not providing accelerations, hence they are in the
buffer earlier.

The unfeasible target for `movel` with the instruction executor seems to
be flaky. Since with `movel` we cannot request a motion running outside
the reachable volume without running into a singularity, we'll have to
check for a protective stop, instead.

This allows cancelling a running motion with the InstructionExecutor. As
executions are blocking, they have to be run in another thread to be
able to be canceled.

This should make it more obvious how to turn on / off the integration
tests.

This seems to be an error in gcov and this occasionally makes our
pipelines fail. As a consequence, we just re-run the job hoping that
doesn't show up as it doesn't seem to be completely deterministic.

Instead we could just ignore that particular error.

And replace them with the PrimaryClient.

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Co-authored-by: Mads Holm Peters <79145214+urmahp@users.noreply.github.com>

There were a couple of build warnings introduced earlier. This fixes
them.