Create a final pipeline (frame comparison CPU and background removal CPU)

[lyuzinmaxim]

In this ticket, we want to combine together several features in a deepstream_pipeline.py. For that, please create a new file called deepstream_pipeline_cpu.py. Features to be included:

• Frames skipping implementation #93 (Probe to compare the frames and drop w/o changes, CPU implementation)
• Implement a modular background removal technique #87 (Probe to remove the background, CPU implementation)
• Modular nvmsgbroker pipeline #95 (Probe to collect and prepare metadata to send to the DB)

DoD:

• An e2e pipeline is functioning