Add a new method to capture errors during the iteration

[gsabran]

The iterator returned by prepare would crash during iteration when it encounters an error at

https://github.com/stephencelis/SQLite.swift/blob/210098546d59678f720e4ef67f8b562acfebbdb0/Sources/SQLite/Core/Statement.swift#L211

This PR proposes a change to add a method to load all of the query's results at once, safely catching possible errors.

[nathanfallet]

@gsabran I merged #1030, does it fix the problem or this PR needs to be merged as well? (because it is related)

[jberkel]

the suggested change is problematic for large queries (memory)

[jberkel]

actually this is already possible with the RowIterator API:

let result = try Array(db.prepareRowIterator(users))

[gsabran]

thanks