Merge branch 'kersplat'

* kersplat: (23 commits)
  Check spelling
  Build pkgdown
  Run checks
  Rename Splotch to Kersplat
  Add Splotch to listSims
  Document Splotch estimation functions
  Document Splotch simulation functions
  Minor Splotch changes
  Add doublets to SplotchSimulate
  Add ambient expression and empty cells to Splotch
  Add BCV adjustment to Splotch
  Add density sampling option for means, lib sizes
  Add violins to comparison plots
  Replace library size log-norm with density
  Fix splotchEstimate example
  Add expression outliers to Splotch
  Fix bug in selectFit
  Add splotchEstimate function
  Simulate counts and organise functions
  Add library size params and simulate cell means
  ...