[MLLIB] [DOC] Seed fix in mllib naive bayes example

Previous seed resulted in empty test data set.

Author: Paweł Kozikowski <mupakoz@gmail.com>

Closes #7477 from mupakoz/patch-1 and squashes the following commits:

f5d41ee [Paweł Kozikowski] Mllib Naive Bayes example data set enlarged

data/mllib/sample_naive_bayes_data.txt

 0,1 0 0
 0,2 0 0
+0,3 0 0
+0,4 0 0
 1,0 1 0
 1,0 2 0
+1,0 3 0
+1,0 4 0
 2,0 0 1
 2,0 0 2
+2,0 0 3
+2,0 0 4
\ No newline at end of file