Merge pull request #1 from Bryukh-Checkio-Tasks/words-finder

Words finder
Merge pull request #2 from Bryukh-Checkio-Tasks/words-finder

grammar fixes
precondition fixes

Removed precondition with case when keywords contain or intersect each other.
key words limitations fixes
Update init.js

Fix the test explanation in the editor.
Merge pull request #3 from Bryukh/patch-2

Update init.js
Merge branch 'master' of https://github.com/AnaPana/checkio-task-words-finder into words-finder
add tests