small fixes to conversion functions to/from Seurat objects

[andrewwbutler]

Changes to importCDS

• convert raw.data slot to a matrix to allow conversion to AnnotatedDataFrame
• subset raw.data slot to only cells that are summarized in meta.data
• more robust check for matrix of integers (could be matrix of 'numeric' class entries but are still integer values) when determining the expressionFamily

Changes to exportCDS

• Use CreateSeuratObject instead of new class constructor so that normalization/scaling procedures are consistent and other slots are populated correctly (cell.names)

[Xiaojieqiu]

Hi Andrew,

Thanks for your pull request! I actually made the changes as you suggested yesterday. But because we are waiting for the monocle to be built on the bioconductor and thus have not replied you back. Sorry about this. I will check your PR and my changes to merge them soon.

Thanks again!

[andrewwbutler]

Ok no worries. Just wanted to make sure you had something to work with. At least in my experience, things tend to get a bit hectic around releases 😃