Add Content Fitting Mode Option on Fancy Button

[bbazukun123]

• Add the optional contentFittingMode option on FancyButton which defaults to default:
  • default: Text and icon content are constrained within the dimensions of the button view as before, with padding accounted for. ie. if content dimensions exceed that of the view - paddings, they will scale down just enough to fit. Otherwise they will remain at their default scale.
  • fill: Text and icon content are scaled proportionally to fill the button view, with padding accounted for but without exceeding dimensions. Here, the optional default scale options will apply on top of the content after the filling is done.
  • none: Text and icon content will always remain at their default scale regardless of the button view dimensions and padding.
• Deprecate the optional ignoreRefitting as it was previously meant to allow for the legacy behaviour of the content fitting which is not desirable. ie. the content will preserve its down scaling and won't reset to its base scale even if the updated button view dimensions are be able to accommodate their base dimensions (Logic remains intact for the rare case of it still being in use).
• Add the contentFittingMode option on the FancyButtonNineSliceSprite example.
• Lint fixes for the examples.