Coupon totals cannot be less than 0

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Discounts higher than the price taxes should = 0

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1.5.2

Merge branch 'master' of github.com:lukepolo/laracart

Return item in coupon

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Breaking Changes!!!!!

All coupons must now have a forItem

which allows us to add coupons on the fly

    $this->laracart->add(
            1,
            'Product with 19% Tax',
            1,
            100,
            [
                \LukePOLO\LaraCart\CartItem::ITEM_TAX => .19,
            ]
        )->addCoupon(new \LukePOLO\LaraCart\Coupons\Fixed('50EUR', 50, [
            'description' => '50EUR',
        ]));

Forgot to add defaults

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Pre Taxed Discount Tax totals fixed

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Added option to say discounts are pre taxed

Merge pull request #227 from lukepolo/stylejs-1238

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Make sure items are an array

Merge pull request #220 from yajra/patch1

Cast items to array.

Updating Tests

Merge pull request #219 from lukepolo/bug/217

Bug/217