Fixes #48

These would sometimes error due to sampling of example dataset

* dropout:
  Use development version
  Run checks
  Add group as a dropout.type option
  Add dropout.type tests
  Add dropout.type to splatSimulate
  Change dropout.present to dropout.type

* master:
  Bump version number
  Add SparseDC tests
  Run checks
  Add SparseDC to listSims
  Add sparseDCEstimate
  Add sparseDCSimulate
  Add SparseDCParams
  Rename params metadata to Params for consistency
  Reset path.from if nGroups changes in SplatParams
  Colourise listSims
  Colourise Params print output
  Improve printing of data.frame parameters
  Improve mean fitting warning in splatEstMean
  Simplify problematic doc links
  Run checks
  Add lib.norm to splatEstimate
  Add lib.norm to splatSimulate
  Add lib.norm parameter to SplatParams
  Use development version

* SparseDC:
  Add SparseDC tests

* SparseDC:
  Run checks
  Add SparseDC to listSims
  Add sparseDCEstimate
  Add sparseDCSimulate
  Add SparseDCParams

Fixes #30

Fixes #36

crayon is the best!

Fixes #17

Also add note if lib sizes estimated to be normal

Fixes #32

* libsizes:
  Run checks
  Add lib.norm to splatEstimate
  Add lib.norm to splatSimulate
  Add lib.norm parameter to SplatParams
  Use development version

* master:
  Add ORCIDs
  Update README