* First take at flattening middleware for simpler code and better perf
* Undo debug prints
* Fix using wrong path in snapshot_from_vfs
* Disable some broken tests
* Re-enable (mistakenly?) disabled CSV test
* Fix some tests
* Update project file tests
* Fix benchmark
* vroom
* Port dir middleware
* Filter rules
* Directory metadata
* Project support
* Enable Lua support
* StringValue support
* CSV
* rbxm, rbxmx, and rbxlx
* JSON models
* Clean up some warnings
* Strip out PathMap
* Unwatch paths when they're reported as removed
* Fix 'rojo upload' behavior
* Upgrade to Insta 0.13.1
* Update dependencies
* Release 0.6.0-alpha.2
* Fix bad merge
* Replace MemoryBackend with InMemoryFs
* Sledgehammer tests into passing for now
* Txt middleware
* Update easy snapshot tests
* Lua tests
* Project middleware tests
* Try to fix test failures by sorting
* Port first set of serve session tests
* Add InMemoryFs::raise_event
* Finish porting serve session tests
* Remove UI code for introspecting VFS for now
* VFS docs
* Drop plugin context on the floor
* Remove redirect from old context to new context
* Pass InstanceContext via & instead of &mut reference
* Re-use context value in ChangeProcessor from metadata
This PR refactors all of the methods on `Vfs` from accepting `&mut self` to
accepting `&self` and keeping data wrapped in a mutex. This builds on previous
changes to make reference count file contents and cleans up the last places
where we're returning borrowed data out of the VFS interface.
Once this change lands, there are two possible directions we can go that I see:
* Conservative: Refactor all remaining `&mut Vfs` handles to `&Vfs`
* Interesting: Embrace ref counting by changing `Vfs` methods to accept `self:
Arc<Self>`, which makes the `VfsEntry` API no longer need an explicit `Vfs`
argument for its operations.
* Change VfsFetcher to be immutable with internal locking
* Refactor Vfs::would_be_resident
* Refactor Vfs::read_if_not_exists
* Refactor Vfs::raise_file_removed
* Refactor Vfs::raise_file_changed
* Add Vfs::get_internal as bits of Vfs::get
* Switch Vfs to use internal locking
* Migrate all Vfs methods from &mut self to &self
* Make VfsEntry access Vfs immutably
* Remove outer VFS locking (#260)
* Refactor all snapshot middleware to accept &Vfs instead of &mut Vfs
* Remove outer VFS Mutex across the board
