3.32.0 - Adds multirow insert method

What's Changed

Adds multirow insert method by @NeedleInAJayStack in #153

This adds functionality to do a multi-row inserts with a single values method call.

Previously, to insert multiple rows a user had to call values repeatedly:

db.insert(into: "planets")
    .columns(["name", "color"])
    .values([SQLBind("Jupiter"), SQLBind("orange")])
    .values([SQLBind("Mars"), SQLBind("red")])
    .run()

This was a bit awkward when inserting rows from an array, where an instance of the builder had to be saved off and edited:

let rows: [[SQLExpression]]  = [[...], [...], ...]
let builder = db.insert(into: "planets")
    .columns(["name", "color"])
for row in rows {
    builder.values(row)
}
builder.run()

db.insert(into: "planets")
    .columns(["name", "color"])
    .values([[SQLBind("Jupiter"), SQLBind("orange")], [SQLBind("Mars"), SQLBind("red")]])
    .run()

let rows  = [[...], [...], ...]
db.insert(into: "planets")
    .columns(["name", "color"])
    .values(rows)
    .run()

…

This patch was released by @gwynne

Full Changelog: 3.31.1...3.32.0