convert_counts_matrix failing with .monoclerc

[rfriedman22]

The develop branch has been updated to source a $HOME/.monoclerc file on load. However, when I call convert_counts_matrix(cds) with no additional arguments, I get the following error because the matrix_control parameter is an empty list:

Error: convert_counts_matrix: invalid matrix_control parameter

I was able to solve it by setting the matrix_control argument to the value set in my rcfile:

convert_counts_matrix(cds, matrix_control = monocle3:::get_global_variable("matrix_control_bpcells_unrestricted"))

I think that this function should look for the global parameter if nothing is specified by the user as input to convert_counts_matrix().