Train model command n_iteration 20 -> 30
In source code `train.py` default Number of iterations  is 30
@@ -280,7 +280,7 @@ p
+row
+cell #[code --n-iter], #[code -n]
+cell option
- +cell Number of iterations (default: #[code 20]).
+ +cell Number of iterations (default: #[code 30]).
+row
+cell #[code --n-sents], #[code -ns]
