don't wrap Authors@R field
update NEWS
add test
Merge pull request #284 from krlmlr/no-wrap-authors-r

don't wrap Authors@R field in the DESCRIPTION file
Fix @describeIn with plain functions

Previously these did not include the function name in the list.
Fixes #285
Merge pull request #286 from jimhester/describeIn_functions

Fix @describeIn with plain functions
Allow describeIn to be used with data documentation

fixes #288
Merge pull request #289 from jimhester/describeIn_data

Allow describeIn to be used with data documentation