Add Array Unterface for createIndex(_:unique:ifNotExists:)

[horita-yuya]

How about adding array interface for createIndex(_:unique:ifNotExists:), in addition to variadic interface?
Inside variadic function the type of the parameter is Array. But it does not accept Array Type.
Isn't it inconvenient a little bit in using it inside some functions like below?

import SQLite

var table: Table
func Hoge(numberColumns: Int...) {
...
table.createIndex(numberColumns) // Error because of variadic.
...
}

Sincerely,

[kireev4art]

It is inconvenient and it’s my fault. I tried to remove controversy between documentation and code.
Please see https://github.com/stephencelis/SQLite.swift/blob/master/Documentation/Index.md#indexes and #666 for more details.