Decide on ranking

for example, check 20th result:

`http://localhost/search?query=%2A%2Akern%0D%0A%2AclefG2%0D%0A%2Ak%5B%5D%0D%0A%3D-%0D%0A4g+dd%0D%0A4d%0D%0A4a+f%0D%0A4c+4b%0D%0A&page=1&rpp=20`

(with `/testdata/palestrina_masses/mid/*` as database)