pan

Add support for complex expressions, a method of creating a child buffer of expressions that can be joined without impacting the buffer of the parent Query.

pan.Insert now allows using a variadic slice, as it no longer distinguishes between the first item to insert and any other items to insert.

Updated to use generics and any from Go 1.18. Also, added SQLiteString() as a method for *Query, allowing first-class support for SQLite outputs, even though they're the same as MySQL outputs.

Insert no longer requires converting slices to []pan.SQLTableNamer before they can be passed as variadic arguments thanks to generics.

*Query.In still requires converting slices to []any before they can be passed in as variadic arguments, as generics can't be used on methods at the moment.

After an extensive rewrite, lots of new tests being added, some benchmarking, an actual README, and a few other tweaks, we're finally ready for our first public release, making pan usable by people who are not-us.