Move over Squirrel.Client code, fix it all up except for UpdateManager
Rewrite UpdateManager

* Remove Filesystem Abstractions
* Rx => async/await
* Nuke the AppDomain stuff
Just use the Log() method
Make all the tests pass by deleting the ones I don't like
Add test files, update namespaces
Create a CIBuild Solution Configuration
Merge remote-tracking branch 'origin/master' into resurrect-client
Comment out a ton of tests and fix up the rest to build
I keep fixing this, why does it come back
Add Runners to solution
Use SearchOption.AllDirectories and EnumerateFiles

Avoids unnecessary allocations (arrays and LINQ) and allows enumerating
through the results immediately without having to wait for arrays to be
allocated, filled, and returned.
Merge pull request #8 from justinvp/enumeratefiles

Utility.GetAllFilesRecursively Improvements
Update README.md
Merge pull request #10 from Squirrel/paulcbetts-patch-1

Update README.md
Make package application sync for now
Pour some await on these tests
Comment out more tests
Merge pull request #7 from Squirrel/resurrect-client

Resurrect UpdateManager
Brutal ripping of code into partial classes - doesn't compile at all
Get CheckForUpdates into its own inner class