Add log compression option to AlignAndFocusPowder

[rosswhitfield]

Description of work

Modify the CompressTolerance parameter and add a parameter CompressBinningMode to allow for logorithmic compression that is now available in CompressEvents. The logic of AlignAndFocusPowder::shouldCompressUnfocused() method should be updated as well since the predicted number of logorithmic compressed events is different than linear compression.

Summary of work

Fixes 5163: Modify AlignAndFocusPowder to take advantage of new capability in CompressEvents

Further detail of work

To test:

Taken from the unit test, you play with the difference between linear and log binning.

ws = CreateSampleWorkspace("Event", "Powder Diffraction", XMin=300, XMax=16666, BinWidth=1.0, NumBanks=1, BankPixelWidth=12, NumEvents=10000)
RotateInstrumentComponent(ws, ComponentName="bank1", Y=1, Angle=90.)
MoveInstrumentComponent(ws, ComponentName="bank1", X=5, Y=-.1, Z=.1, RelativePosition=False)

out  = AlignAndFocusPowder(ws, Dspacing=False, PreserveEvents=True, CompressTolerance=-1e-5, ResampleX=1000)
out2 = AlignAndFocusPowder(ws, Dspacing=False, PreserveEvents=True, CompressTolerance=1e-5, ResampleX=1000)

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[peterfpeterson]

Looks good to me. This will allow more people to use the feature in AlignAndFocusPowder and integrating it into calling workflow algorithms.