Detect and report when the limit for maximum number of documents in a single index is exceeded [LUCENE-4105]

#5176 documents the limit for maximum number of documents in a single index, but it is highly desirable to have Lucene detect when this limit is reached and throw a sensible exception for the user.

I am not sure of the implementation details, but it seems as if IndexWriter.addDocument, addDocuments, addIndexes, and updateDocuments would be the APIs from which a new exception, call is MaxDocumentException would be thrown.

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Migrated from [LUCENE-4105](https://issues.apache.org/jira/browse/LUCENE-4105) by Jack Krupansky

Start by tracing the IndexWriter.addDocument, addDocuments, addIndexes, and updateDocuments APIs named in the issue, and review #5176 for the documented maximum. Determine how exceeding the limit should be detected and reported through a new MaxDocumentException; done means the affected APIs consistently provide that sensible exception.

Written by the indexing model from the issue text.