Review which arguments should use str.lower transformation

[hayleycodes]

Some tag arguments use the str.lower transformation to convert them to lower case. All arguments should be reviewed to determine whether they should be using this parser as I suspect it's use has been inconsistent.

For example, there are some arguments that accept only true/false values but only work if they are in lower case, and in these cases it would make sense to make use of the str.lower transformation.