Adding median_quartiles to pairwise_test_cont()

[lemireg]

A number of requests have come in for the testing comparison tables to include Median (25%, 75%) quartiles instead of the current output Median (Min, Max) as a part of the output of pairwise_test_cont() function.

[lemireg]

Bryan's comments:

• you could get away with Group1_q1 instead of Group1_first_quart (and using q1 or q3 elsewhere)
• you should check in on the type argument for quantile() function and double-check what the standard is for SAS and hvtn. this is something we've run into in the past when trying to sync results. might be ok to keep the default.
• you might also force names = FALSE
• makes sure to update the tests too!

[slager]

Feel free to re-tag me if/when this needs another review!

[lemireg]

FYI for one of the tests I am simply dropping the column rather than editing the fixed data. We can discuss at our next meeting if this is the preferred approach. I didn't want to change the fixed data and break other things!

[mayerbry]

looks great! revert the two .Rds whitespace changes in the man/folder

[slager]

I'm finished making commits here! Please double check all looks as expected prior to merging.