This makes the mode detection consistent. Without this: Sometimes
Emacs buffer used to use rustic mode and sometimes rust-ts-mode.

The source code is this:

fn main() {
                       let v = vec![1, 2, 3];
                       v[99];
}

While the code is incorrect, it does not have any compile error.

Fix possible babel test failures

Add docs for tree-sitter

Fix bugs related to tree sitter integration

Make rustic-cargo-clippy remember it's universal arguments

Fix flaky clippy test

Update docs

Improve minibuffer entry population for build and clippy

Fix flaky tests

Fixes psibi#19

Update rustic-cargo-test to remember it's universal argument

rustic-recompile will remember universal arguments passed

Firstly, use `add-to-list` rather than `setq` so that existing
archives aren’t affected.  In particular, Emacs includes NonGNU
ELPA on the list and current instructions remove that archive.

Secondly, prefer https over http when specifying URL of MELPA.

Update package-archives modification code in README

Currently rustic will override the default-directory to the workspace root after
a compilation is finished. This enables it to correctly find the paths in error
messages. But it also means that if you rerun a command it will rerun in the
root crate instead of the original one.

This change adds a new variable to track the original directory and resets it
when we rerun.