Added stitchtility and playground

stitch_project/api/Stitch/Stitchtility.py

+def frequencyHzToDphi(frequency):
+    dphi = int(frequency/0.18626451492)
+    if dphi <= 1:
+        return 1
+    if dphi >= 2**22:
+        return 2**22-1
+    else:
+        return dphi
+
+def rampHzSqToDdphi(rampHzSq):
+    ddphi = int(rampHzSq/2.22044604921)
+    if ddphi <= 1:
+        return 1
+    if ddphi >= 2**22:
+        return 2**22-1
+    else:
+        return ddphi
+
+def DeltaDphiAndDdphiToNsweep(DeltaDphi, Ddphi):
+    return int(DeltaDphi/(Ddphi*2**-23))
+
+def numPeriodsToNringup(numPeriods, frequencyHz):
+    return int(numPeriods*100.0e6/frequencyHz)
+
+def numPeriodsToNmeas(numPeriods, frequencyHz):
+    return int(numPeriods*100.0e6/frequencyHz)