Show errors in the parsing of a file when using a tree-sitter grammar in Atom.
It will use the editor's parser, so no tree-sitter dependencies are required. It will apply itself to all editors using tree-sitter grammars, keeping track of grammar changes and updating accordingly.
Linting is redone each time TextEditor.onDidStopChanging() calls it.
Right now, errors are given a generic Error! error, and missing fields are given a warning. I tried using the .isMissing() property of the nodes, but it didn't seem to work. Instead, it will throw a missing warning when an error is detected somewhere inside the node, and the range is zero width.