Overhaul TokenStream ICloseable/IDisposable Patterns, #271

[paulirwin]

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Overhaul TokenStream ICloseable/IDisposable Patterns

Fixes #271

Description

This pull request focuses on refactoring the codebase by replacing the Dispose method with the new ICloseable interface's Close method in all provided TokenStream implementations to make them reusable. None of the implementations in our codebase need a non-reusable cleanup method, however, in discussion in #271, it was determined that there are possible use cases in which a custom TokenStream implementation might need to have their instance Disposed when the owning Analyzer (with stored values set by a ReuseStrategy) is disposed, so we have retained the IDisposable pattern as well. This PR also ensures that those values are disposed by way of DisposableThreadLocal and TokenStreamComponents disposing of their values.

Remaining draft PR TODOs:

• Make PrefixTreeStrategy.CellTokenStream reusable
• Make MemoryIndex.TokenStreamAnonymousClass<T> reusable
• Determine if we can fix the failing test in TokenStream.IncrementToken() is called after Dispose() is called #271
• Split out any other requirements as separate issues if possible (or include here)