Update NEWS.md

Fix those damned URLs

Update pkgdown site

Update .gitignore

Merge branch 'master' of https://github.com/quanteda/readtext

Update cran-comments.md

Update CRAN comments

Exclude large test files

This was necessary to get the tarball <5MB, a requirement for CRAN.  It went from >8MB to 2.2MB after this change.

- added tests/data/encoding to .Rbuildignore
- moved tests that use the encoding files to separate tests .R file, and added that file to .Rbuildignore