Note that this commit holds off on modifying the Cargo.toml until some
minor fixes have been merged into GapBuffer proper. A subsequent commit
will change this to point to the correct commit. Do not merge until the second commit.
Note: yes, Vec each time we call lines().next() is dumb, but it works. If it negatively impacts performance, we can write something smarter (e.g. rewrite lines() to return iterators rather than vectors or slices).
Note that this commit holds off on modifying the Cargo.toml until some minor fixes have been merged into GapBuffer proper. A subsequent commit will change this to point to the correct commit. Do not merge until the second commit.