Added next chapter

Froussios · Froussios · commit 0e95220590a4 · 2015-04-19T21:44:08.000+02:00
diff --git a/Part 4 - Concurrency/3. Sequences of coincidence.md b/Part 4 - Concurrency/3. Sequences of coincidence.md
@@ -235,4 +235,4 @@ You can also implement `groupJoin` with `join` and `groupBy`. Doing so would req
 
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