Provides classes for working with a repository of citable texts.
The highest-level class is the TextRepository. It contains
a Catalog with metadata about texts and a Corpus of textual data.
The Corpus is simply a Vector of CitableNode objects.
The library supports reading from and serializing to CEX format.
In the JVM branch, the TextRepositorySource object has functions for
creating a repository from a cataloged set of texts in local files.