Updating ap's description

[JeffDownie]

Fix for issue #2002 - ap function dispatches to wrong argument.

From @ davidchambers:

Ramda currently targets v0.3.0 of the Fantasy Land specification, which explains why the argument order does not match that of the current version of the specification. #1900 will update Ramda to a more recent version of the specification, if merged.

[davidchambers]

🌳

[customcommander]

@davidchambers @CrossEye I fixed the merge conflict. The original pull request was trying to update src/ap.js which we don't have anymore. I changed it to update source/ap.js instead.