Add list of 10k most frequent words

From http://www.cl.ut.ee/ressursid/sagedused/index.php?lang=et
Made the following changes:
  - removed DOS newlines
  - kept only the first 3 columns
  - converted to utf8
  - removed the first line (header) and the last line (empty)
  - fixed š and ž
  - sorted

Also added script that does a full join of the frequency data and paradigm test results.
NB: does not work yet correctly!