Capitalization for embeddings needs fixing

[innesbre]

If embedding names are capitalized, getEmb fails.

sce <- SingleCellExperiment(
  assays=list(counts=matrix(nrow=10,ncol=10),
              logcounts=matrix(nrow=10,ncol=10),
  reducedDims=list(PCA=matrix(nrow=10,ncol=10),
                   TSNE=matrix(nrow=10,ncol=10)
)
seur <- as.Seurat(sce)

getEmb(seur,"TSNE") #fails
getEmb(seur,"tsne") #fails