Reimplemented the fix from #2183 to fix building WASM files with Docker
on Windows again. The --workdir argument gives a path inside the Docker
container, so it must use forward slashes regardless of the default path
separator on the host OS.
The `tree-sitter-loader` crate currently always pulls
`tree-sitter-highlight` and `tree-sitter-tags` as dependencies.
However, apart from the tree-sitter CLI, most clients will not need both
of these libraries.
This commit makes the dependencies optional, but still includes them by
default in order not to break the backward compatibility.
This patch adds the `tree-sitter-config` crate, which manages
tree-sitter's configuration file. This new setup allows different
components to define their own serializable configuration types, instead
of having to create a single monolithic configuration type. But the
configuration itself is still stored in a single JSON file.
Before, the default location for the configuration file was
`~/.tree-sitter/config.json`. This patch updates the default location
to follow the XDG Base Directory spec (or other relevant platform-
specific spec). So on Linux, for instance, the new default location is
`~/.config/tree-sitter/config.json`. We will look in the new location
_first_, and fall back on reading from the legacy location if we can't
find anything.
This patch adds a new `tree-sitter-loader` crate, which holds the CLI's
logic for finding and building local grammar definitions at runtime.
This allows other command-line tools to use this logic too!
