roperators 1.2.0

• Cleaned up roxygen comments, DESCRIPTION, and NAMESPACE files.
• Added a NEWS.md file to track changes to the package.
• New complete cases functions (length_cc(), min_cc(), max_cc(), range_cc(), all_cc(), any_cc(), sum_cc(), prod_cc(), mean_cc(), median_cc(), var_cc(), cov_cc(), cor_cc(), sd_cc(), weighted.mean_cc(), quantile_cc(), IQR_cc(), mad_cc(), rowSums_cc(), colSums_cc(), rowMeans_cc(), colMeans_cc()) that set default argument to standard base/stats functions for only calculating on complete cases.
• New get_os(), is.os_mac, is.os_win, is.os_lnx, and is.os_unx helper functions to quickly determine operating system.
• New is_txt_file(), is_csv_file(), is_excel_file(), is_r_file(), is_rdata_file(), is_rda_file(), is_spss_file(), and check_ext_against() functions to quickly determine if file has specific file extensions.
• New is.R_Revo() and is.RStudio() functions to determine whether Revolution R and RStudio are installed.
• New n_unique() function to count unique items and n_unique_cc() version for complete cases.
• New is.constant() and is.binary() functions to indicate whether a vector is constant (contains only ONE value type, ignoring NA) or binary (contains at most TWO value types, ignoring NA).
• New get_most_frequent() function to get most frequent thing(s) in x.
• New get_most_frequent_word() function to get most frequent word from string.
• New get_nth_word() function to get nth word from string
• New as.class() pipe-able function for arbitrary class conversions
• New paste_()is the same as paste0 but uses an underscore to separate
• New cat0() is analogous to paste0 but for cat
• New catN() is the same as cat0 but automatically inserts a new line after the cat
• New paste_series() paste a series of things with a conjunction
• New paste_oxford() shortcut for paste_series as oxford comma