Pipette and "On Preview Widgets" branch. See issue 227

The pipette part is already working quite nice but need to be finished. The widgets part needs more work...

rtdata/profiles/Generic/High-Key.pp3

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+[Version]
+AppVersion=4.0.12
+Version=316
+
+[Exposure]
+Auto=true
+Clip=0.02
+Compensation=0
+Brightness=0
+Contrast=0
+Saturation=-10
+Black=0
+HighlightCompr=0
+HighlightComprThreshold=33
+ShadowCompr=50
+CurveMode=Standard
+CurveMode2=Standard
+Curve=2;0.105;0.25;0.75;15;60;30;-70;
+Curve2=0;
+
+[HLRecovery]
+Enabled=false
+Method=Blend
+
+[Channel Mixer]
+Red=100;0;0;
+Green=0;100;0;
+Blue=0;0;100;
+
+[Black & White]
+Enabled=false
+Method=Desaturation
+Auto=false
+ComplementaryColors=true
+Setting=NormalContrast
+Filter=None
+MixerRed=33
+MixerOrange=33
+MixerYellow=33
+MixerGreen=33
+MixerCyan=33
+MixerBlue=33
+MixerMagenta=33
+MixerPurple=33
+GammaRed=0
+GammaGreen=0
+GammaBlue=0
+LuminanceCurve=0;
+BeforeCurveMode=Standard
+AfterCurveMode=Standard
+BeforeCurve=0;
+AfterCurve=0;
+
+[Luminance Curve]
+Brightness=0
+Contrast=5
+Chromaticity=-10
+AvoidColorShift=true
+RedAndSkinTonesProtection=0
+LCredsk=true
+LCurve=0;
+aCurve=0;
+bCurve=0;
+ccCurve=0;
+chCurve=0;
+lhCurve=0;
+hhCurve=0;
+LcCurve=0;
+ClCurve=0;
+
+[Vibrance]
+Enabled=false
+Pastels=50
+Saturated=50
+PSThreshold=0;75;
+ProtectSkins=false
+AvoidColorShift=true
+PastSatTog=true
+SkinTonesCurve=0;
+
+[Color appearance]
+Enabled=false
+Degree=90
+AutoDegree=true
+Surround=Average
+AdaptLum=16
+Badpixsl=0
+Model=RawT
+Algorithm=JC
+J-Light=0
+Q-Bright=0
+C-Chroma=0
+S-Chroma=0
+M-Chroma=0
+J-Contrast=0
+Q-Contrast=0
+H-Hue=0
+RSTProtection=0
+AdaptScene=2000
+AutoAdapscen=true
+SurrSource=false
+Gamut=true
+Datacie=false
+Tonecie=false
+CurveMode=Lightness
+CurveMode2=Lightness
+CurveMode3=Chroma
+Curve=0;
+Curve2=0;
+Curve3=0;
+
+[EPD]
+Enabled=false
+Strength=0.25
+EdgeStopping=1.3999999999999999
+Scale=1
+ReweightingIterates=0
+
+[Shadows & Highlights]
+Enabled=false
+HighQuality=false
+Highlights=10
+HighlightTonalWidth=80
+Shadows=10
+ShadowTonalWidth=80
+LocalContrast=0
+Radius=30
+
+[Gradient]
+Enabled=false
+Degree=0
+Feather=25
+Strength=0
+CenterX=0
+CenterY=0
+
+[PCVignette]
+Enabled=false
+Strength=0
+Feather=50
+Roundness=50
+
+[HSV Equalizer]
+HCurve=0;
+SCurve=0;
+VCurve=0;
+
+[RGB Curves]
+LumaMode=false
+rCurve=0;
+gCurve=0;
+bCurve=0;
+