make database.example.yml use sqlite3
add install to README.md
remove README.rdoc
wrap install instructions in preformat
expand readme
fix problem with links to papers
Merge pull request #13 from mchelen/patch-1

expand readme
switch to normal API again
Don't enforece PLOS dois
Don't enforece PLOS dois
include java requirement
link to install guide on wiki
Merge pull request #21 from mchelen/patch-2

update readme