OPENNLP-1623: Add more test cases for Coref component

[mawiesne]

Change

• adds a ton of new test classes
• adjusts TrainModel interface to return the trained model
• fixes several undetected class cast bugs due to '@SuppressWarnings("unchecked")' cover-up
• makes CorefTrainerTest (somehow) pass
• makes classes named Enum be actual enums

Code-Coverage

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[rzo1]

Overall, it looks good to me. More tests, less bugs ;-)

I have added a question regarding the source (and license?) of the huge acronym txt file.

[rzo1]

Looks like this is taken from: https://catalog.ldc.upenn.edu/desc/addenda/LDC2003T13.txt
In this case, we cannot claim, that it is ASLv2 license (had the same thing in StormCrawler Incubator with external sources). It seems "LDC User Agreement for Non-Members" applies as a license here which would be incompatible with ASLv2 (see commercial section of that PDF).

[rzo1]

I would suggest to re-create that file with arbitrary values (than we can claim ASLv2 for it).

[rzo1]

<!--
   Licensed to the Apache Software Foundation (ASF) under one
   or more contributor license agreements.  See the NOTICE file
   distributed with this work for additional information
   regarding copyright ownership.  The ASF licenses this file
   to you under the Apache License, Version 2.0 (the
   "License"); you may not use this file except in compliance
   with the License.  You may obtain a copy of the License at

     http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing,
   software distributed under the License is distributed on an
   "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   KIND, either express or implied.  See the License for the
   specific language governing permissions and limitations
   under the License.    
-->
<!--
This SGML file is based on the structure of https://catalog.ldc.upenn.edu/LDC2003T13
-->
<DOC>
<DOCNO>  123456-7890. </DOCNO>
<CODER> LoremIpsumCorp </CODER>
<DD> = 123456 </DD>
<AN> 123456-7890. </AN>
<HL> Lorem Ipsum:
@  Dolor Sit Amet Consectetur
@  ---
@  Adipiscing Elit, Sed Do Eiusmod
@  Tempor Incididunt Ut Labore
@  ----
@  By Lorem Ipsum
@  Placeholder Text Author </HL>
<DD> 12/12/21 </DD>
<SO> LOREM IPSUM TIMES (LIT) </SO>
<CO> UNKNOWN </CO>
<IN> PLACEHOLDER TOPICS (PTP)
TEMPORARY SUBJECTS (TMP) </IN>
<GV> FAKE DEPARTMENT (FD)
DUMMY ORGANIZATION (DO) </GV>
<DATELINE> LOREMTOWN  </DATELINE>
<TXT>
<p>
<s> Lorem ipsum dolor sit amet, consectetur adipiscing elit. </s>
</p>
<p>
<s> Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. </s>
<s> Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. </s>
</p>
<p>
<s> Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. </s>
<s> Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. </s>
</p>
<p>
<s> Phasellus faucibus scelerisque eleifend donec pretium vulputate sapien. </s>
<s> Ultrices dui sapien eget mi proin sed libero enim. </s>
</p>
<p>
<s> Non arcu risus quis varius quam quisque id diam vel. </s>
</p>
<p>
<s> Amet nisl suscipit adipiscing bibendum est ultricies integer quis. </s>
<s> Elit eget gravida cum sociis natoque penatibus et magnis dis. </s>
</p>
<p>
<s> Orci eu lobortis elementum nibh tellus molestie nunc non. </s>
<s> Vitae ultricies leo integer malesuada nunc vel risus commodo. </s>
</p>
<p>
<s> Ultricies mi quis hendrerit dolor magna eget est lorem ipsum. </s>
</p>
</DOC>

This follows the format of the file, but is arbitrary, generated content just following the structure to be testable.