Improve if directive formatting

[belav]

Some things that don't work yet.

1. nested directives
2. if the final else needs a specific combination, that won't be in the set
3. we don't actually look at not's correctly. Meaning #IF !ONE && TWO is parsed as ONE TWO, instead of just TWO
4. related, for something like #IF ONE || TWO we only need one of the two symbols
5. we may want to allow specifying symbolSets by file
6. Unable to format when using if directives that contain the end of statements #121

[belav]

https://github.com/belav/aspnetcore/blob/main/src/ProjectTemplates/Web.ProjectTemplates/content/BlazorServerWeb-CSharp/Startup.cs has some good examples

[belav]

https://stackoverflow.com/questions/25789994/microsoft-solver-foundation-sat-cnf