Double arrow addition to pattern library

[austinalbin]

Adding in these svgs to add to the FEC pattern library. These are double arrows, used on FECfile+ for the date picker, allowing the user to navigate 1 year forward or back (as opposed the single arrow that navigates 1 month).

Add icon: double arrow navigation left
Add icon: double arrow navigation right

possible name: .i-double-arrow-right and .i-double-arrow-left

[rfultz]

Will do. Their names will be arrow-left-double and arrow-right-double to keep them in line with the current arrows