Optimize single line body methods

[angelolloqui]

Kotlin allows for = methods instead of { return.

Example:

func mapToUserItem(user: User) -> UserItem {
    return UserItem(name: user.fullName)
}

Translates to:

fun mapToUserItem(user: User) : UserItem {
    return UserItem(name = user.fullName)
}

But could be:

fun mapToUserItem(user: User)  =
    UserItem(name = user.fullName)

[angelolloqui]

Fixed with e0a49e4