Make the print message more similar to the python print message

[rcannood]

R version:

library(anndataR)
read_h5ad("inst/extdata/example.h5ad", to = "InMemoryAnnData")

class: InMemoryAnnData
dim: 50 obs x 100 var
X: dgRMatrix
layers: counts csc_counts dense_X dense_counts
obs: Float FloatNA Int IntNA Bool BoolNA n_genes_by_counts
  log1p_n_genes_by_counts total_counts log1p_total_counts leiden
var: String n_cells_by_counts mean_counts log1p_mean_counts
  pct_dropout_by_counts total_counts log1p_total_counts highly_variable
  means dispersions dispersions_norm

Python:

import anndata as ad
ad.read_h5ad("inst/extdata/example.h5ad")

AnnData object with n_obs × n_vars = 50 × 100
    obs: 'Float', 'FloatNA', 'Int', 'IntNA', 'Bool', 'BoolNA', 'n_genes_by_counts', 'log1p_n_genes_by_counts', 'total_counts', 'log1p_total_counts', 'leiden'
    var: 'String', 'n_cells_by_counts', 'mean_counts', 'log1p_mean_counts', 'pct_dropout_by_counts', 'total_counts', 'log1p_total_counts', 'highly_variable', 'means', 'dispersions', 'dispersions_norm'
    uns: 'Bool', 'BoolNA', 'Category', 'DataFrameEmpty', 'Int', 'IntNA', 'IntScalar', 'Sparse1D', 'String', 'String2D', 'StringScalar', 'hvg', 'leiden', 'log1p', 'neighbors', 'pca', 'rank_genes_groups', 'umap'
    obsm: 'X_pca', 'X_umap'
    varm: 'PCs'
    layers: 'counts', 'csc_counts', 'dense_X', 'dense_counts'
    obsp: 'connectivities', 'distances'