* Update free-programming-books-fi.md
* Fixed a link to author's own page
Found the original link from author's own page so there's no need to link to ResearchGate.
* Newline fix
We had a variety of ways to denote Wikibooks. It seemed appropriate to add "wikibooks" as the "author" and remove "wikibook" from the title, since the books don't use "wikibook" in their titles.
Timo Salomäki
Seth
Eric Hellman
Janne Räisänen