spell_check_package() to include NEWS and ChangeLog too

[HenrikBengtsson]

spell_check_package() checks NEWS.md but not plain-text NEWS files. Please consider adding that. It's probably as simple as adding NEWS to the list of files recognized.

[HenrikBengtsson]

In addition to NEWS, there's also the ChangeLog file that's officially acknowledged by R, cf. WRE. One may also wanna include LICENSE and LICENCE here.

It's the following file grep pattern that needs to be updated:

spelling/R/spell-check.R

Lines 77 to 78 in fc619ee

	root_files <- list.files(pkg$path, pattern = "(readme|news|changes|index).r?md",
	ignore.case = TRUE, full.names = TRUE)

Related: BTW, that reg expr should probably also be protected with a trailing $ to avoid pickup up for instance *.md~ backup files. Also, the period can be escaped, e.g. \\. or [.].

[ethanplunkett]

Possibly consider allowing users to specify a list of non-standard files to add to the check via a file analogous to ./inst/WORDLIST. This would be a compliment of #63 (excluding specific files).

I came here hoping to find a way of adding ./.github/CONTRIBUTING.md but imagine there might be lots of package specific files. One of my package has some template markdown files in ./inst/ that are unique to it.