Add Counter Input examples

[WayneDroid]

• [x] This contribution adheres to CONTRIBUTING.md.

What does this Pull Request accomplish?

• renamed existing CI examples.
• added count event examples.
• added frequency measurement examples.
• added frequency waveform with implicit timing examples.

Why should this Pull Request be merged?

Add CI examples for release 1.0.

What testing has been done?

run poetry run pytest tests/ -q - pass

run CI examples on physical device PXIe-6363:

C:\dev\repo2\nidaqmx-python>poetry run python examples/counter_in/cnt_dig_buff_cont_ext_clk.py                    
Continuously polling. Press Ctrl+C to stop.
Acquired data: 1000 samples. Total 4000.
Acquired 4000 total samples.

C:\dev\repo2\nidaqmx-python>poetry run python examples/counter_in/cnt_dig_event.py            
Continuously polling. Press Ctrl+C to stop.
Acquired count: 2798

C:\dev\repo2\nidaqmx-python>poetry run python examples/counter_in/cont_acq_freq_wfm_impl_time.py
Continuously polling. Press Ctrl+C to stop.
Acquired data: 1000 samples. Total 5000.
Acquired 5000 total samples.

C:\dev\repo2\nidaqmx-python>poetry run python examples/counter_in/cont_acq_freq_wfm_large_range_2_cnt_impl_time.py
Continuously polling. Press Ctrl+C to stop.
Acquired data: 1000 samples. Total 18000.
Acquired 18000 total samples.

C:\dev\repo2\nidaqmx-python>poetry run python examples/counter_in/read_freq_low_freq_1_cnt.py   
Acquired frequency: 999.99 Hz

C:\dev\repo2\nidaqmx-python>poetry run python examples/counter_in/read_pulse_freq.py         
Acquired data:
Frequency: 999.99 Hz
Duty cycle: 50.00%