Vim plugin

### How it should work

- Separate repository (name it sql-lint.vim)
- Has an `sql` ftplugin which should contain the following

```
"Double check the syntax for +=, just assuming that's correct
set makeprg+=sql-lint\ --file=%
set errorformat+=%f:%l\ %m
```

- Should install semi-automagically. In `vim-plug` it should look like this:

```
Plug 'joereynolds/sql-lint.vim', {'do': 'npm install'}
```

This will do `npm install sql-lint` under the hood.

A nice to have is that it would work in non `.sql` files.

i.e. for PHP, it should try its best to recognise an SQL query in the buffer and run sql-lint on that query.