Malformed input data, unexpected `NA`s are present

[Ahmedalaraby20]

Hi Ryan,

So,

data_list[[i]] <- import_vdj(input = data_list[[i]], vdj_dir = vdjdir[[i]], filter_paired  = T, include_mutations = T, include_constant = TRUE, data_cols = c("cdr1", "cdr2"))

gives me

Malformed input data, unexpected `NA`s are present. Did you modify the `cellranger` output files? `import_vdj()` requires files that
  are in the format generated by `cellranger`. If you are having trouble loading your data, please file an issue at

However,

data_list[[i]] <- import_vdj(input = data_list[[i]], vdj_dir = vdjdir[[i]], filter_paired  = T, include_mutations = T, include_constant = TRUE)

works well,

There are some NA in the cdr1 and cdr2 columns once I replaced them it worked well.

Sorry for posting a lot I hope this helps improve the package filtered_contig_annotations.csv