Change p to params throughout

[bstaton1]

This will clarify the purpose of that argument.

Will be a big job, as most functions contain this argument in one way or another. Changes will need to be made to help files, vignettes, and the readme for the package.

May also want to include something saying that the p argument was deprecated.

FUNCTION NAMES

• get_p -> get_params
• match_p -> match_params
• base_p -> drop_index

ARGUMENTS

• density_plot (p_one -> param)
• trace_plot (p_one -> param)
• diag_plots
• match_params
• post_remove
• post_subset
• post_summ
• vcov_decomp

VIGNETTE

• include changes in naming to the vignette