Support Laravel 5.5

Support for L5.5 #97

Added New Methods

Refer to this: 4e5716f

Laravel 5.4 Support

Merge pull request #82 from frezno/master

Changing share to singleton -> for Laravel 5.4 support

FIXES AND IMPROVEMENTS

Solves Issue: #27 , #28

Added new condition method

Added new condition method: $condition->getAttributes(); See: #19

Added 2 new useful cart APIs

Cart API added:

1.) Cart::getTotalQuantity() from requests:
#13
#17

2.) Cart::addItemCondition($productId, $itemCondition)
#16

Bug Fixes

fixed removeItemCondition() not removing the condition if the condition added on the item was not in an array format..

2 New Cart API when dealing conditions with its type

2.2.0

Updated docs for 2 new Cart API

Revamp updating an existing item's quantity on cart

2.1.1

Update README.md

Added two new useful methods..

2.1.0

Update README.md