OPENNLP-1029: Add tests for InsufficientTrainingDataException.

[jzonthemtn]

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[smarthi]

replace Integer.toString() with String.valueOf() ??

[jzonthemtn]

I'll update usages in these tests to just use strings like "100" and "5".

[coveralls]

Coverage increased (+0.01%) to 56.27% when pulling a16cd51 on jzonthemtn:OPENNLP-1029 into f1f2413 on apache:master.

[coveralls]

Coverage increased (+0.01%) to 56.742% when pulling 6b3f5a4 on jzonthemtn:OPENNLP-1029 into 45ea3f7 on apache:master.

[smarthi]

+1 lgtm, will merge this