* Make our rust tests use per-thread config rather than global static
This lets our unit tests run in parallel. I also moved our "integration"
tests back to be unit tests for now.
This also exposes a network mocking abstraction.
I've added an incomplete test of applying a full patch. Still
needs some work to complete.
* Finish making the patch success test work
* Changed our test config to use println instead of info/error, etc. so that tests show output on failure (there might be a better way?)
Unfortunately macro_use (which is the way we were causing error!, info! etc to appear everywhere with only one global import before, only works on crates not on std, so I had to be explicit with my imports per-file.
* Add a function to build a fake zip file, because that's what the updater currently expects. Better would be for us to move to a AssetManager system I suspect, then the updater would ask the asset manager for the libapp.so and we'd return it instead of having to go through writing out a zip file.
* Added a string_patch.rs tool and shared code between that and the patch tool. This made it possible/easy for me to generate the necessary binary patches as well as needed hashes to pretend to be the patch server.
* Added one simple test of the patch tool core logic.
In total we're now above 80% coverage of our rust code after this.
* remove stray comment
Eric Seidel