note that drivers may not be automatically entered in odbcinst.ini on install

[simonpcouch]

Much of the documentation I've found (pyodbc docs, our docs, for example) seems to suggest that brew installing a driver will enter appropriate entries in the odbcinst.ini noted in odbcinst -j automatically. I've only seen this happen once after installing a few different drivers; it may be worth noting how to locate the install after brew install. I've been using brew info to get started.

[hadley]

Note the wrapper in #634 (comment) that would be straightforward to adapt for any backend.