Changed BackgroundWorkers to async await

[tombogle]

This change is 

[andrew-polk]

Reviewed 4 of 4 files at r1.
Reviewable status: all files reviewed, 3 unresolved discussions (waiting on @AndrewChristensenFCBH and @tombogle)

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GlyssenEngine/Project.cs, line 1466 at r1 (raw file):

ParseAndIncludeBooks

Should this be named ParseAndIncludeBooksAsync?

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GlyssenEngine/Project.cs, line 1528 at r1 (raw file):

ProjectState = ProjectState.UsxComplete | (ProjectState & ProjectState.WritingSystemRecoveryInProcess);

Should this line get moved into GuessAtQuoteSystem?
It doesn't matter now because this is the only caller. But someone looking just at the (albeit private) API might think GuessAtQuoteSystemAsync and GuessAtQuoteSystem are the same except for synchronicity.

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GlyssenEngine/Project.cs, line 1549 at r1 (raw file):

m_projectMetadata.ParserVersion = kParserVersion;
			ProjectState = ProjectState.Parsing;

Same comment as for GuessAtQuoteSystemAsync above.

[tombogle]

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GlyssenEngine/Project.cs, line 1466 at r1 (raw file):

Previously, andrew-polk wrote…

ParseAndIncludeBooks

Should this be named ParseAndIncludeBooksAsync?

Could be. I only added the Async suffix for the methods where I needed a synchronous and asynchronous version. Not even sure this branch is a "keeper"....

[tombogle]

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GlyssenEngine/Project.cs, line 1528 at r1 (raw file):

Previously, andrew-polk wrote…

ProjectState = ProjectState.UsxComplete | (ProjectState & ProjectState.WritingSystemRecoveryInProcess);

Should this line get moved into GuessAtQuoteSystem?
It doesn't matter now because this is the only caller. But someone looking just at the (albeit private) API might think GuessAtQuoteSystemAsync and GuessAtQuoteSystem are the same except for synchronicity.

Yes it should. There is another caller.

[andrew-polk]

Reviewed 1 of 1 files at r2.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @andrew-polk and @AndrewChristensenFCBH)