[qblox backend] Reset NCO clock phase on every measurement (#296, QAE-150)

Explanation of changes

As described in #296 (closed) it is desirable to have the phase of the measurement clock to be set to zero at the start of every measurement. A reset_clock_phase parameter is introduced to the device_config and can be set to True/False directly through a BasicTransmonElement.

For example:

q0.measure.reset_clock_phase(True)
device_cgf = quantum_device.generate_device_config()

schedule = Schedule(f"Test schedule")
schedule.add(X90("q0"))
schedule.add(Measure("q0"))

compiled_schedule = qcompile(schedule, device_cgf, hardware_cfg)

generates the following QASM code (on qblox devices) for seq0 on the qrm

          wait_sync     4                                                
          upd_param     4                                                
          set_mrk       15         # set markers to 15                   
          wait          4          # latency correction of 4 + 0 ns      
          move          1,R0       # iterator for loop with label start  
  start:                                                                 
          reset_ph                                                       
          upd_param     4                                                
          wait          20         # auto generated wait (20 ns)         
          reset_ph                                                       
          set_awg_gain  32,0       # setting gain for Measure q0         
          play          0,1,4      # play Measure q0 (160 ns)            
          wait          116        # auto generated wait (116 ns)        
          acquire       0,0,4                                            
          wait          296        # auto generated wait (296 ns)        
          loop          R0,@start                                        
          set_mrk       0          # set markers to 0                    
          upd_param     4                                                
          stop

while setting q0.measure.reset_clock_phase(False) will generate

          wait_sync     4                                                
          upd_param     4                                                
          set_mrk       15         # set markers to 15                   
          wait          4          # latency correction of 4 + 0 ns      
          move          1,R0       # iterator for loop with label start  
  start:                                                                 
          reset_ph                                                       
          upd_param     4                                                
          wait          20         # auto generated wait (20 ns)         
          set_awg_gain  32,0       # setting gain for Measure q0         
          play          0,1,4      # play Measure q0 (160 ns)            
          wait          116        # auto generated wait (116 ns)        
          acquire       0,0,4                                            
          wait          296        # auto generated wait (296 ns)        
          loop          R0,@start                                        
          set_mrk       0          # set markers to 0                    
          upd_param     4                                                
          stop

Note that q0.measure.reset_clock_phase(True) is the default behavior. Also, note that currently the resetting of the NCO clock phase is only supported by the qblox backend.

Under the hood this is achieved by implementing a new class operations.pulse_library.ResetClockPhase which is added as a pulse right before a measurement pulse during compilation if q0.measure.reset_clock_phase is set to True. Later on this pulse is translated to Q1ASM code via backends.qblox.operation_handling.virtual.NcoResetClockPhaseStrategy, which simply adds a line reset_ph to the existing q1asm program.

Note

Real signals can be output on odd outputs in real mode but lead to a 90-degree phase shift. The current fix does not take that into account, but the clock phase is constant across measurements, so not necessarily a problem.

Closes #296 (closed)

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