Fix autofix of inset/margin/padding with 4 physical values

[zfeher]

Fixes #32

inset/margin/padding expects top-right-bottom-left ordering physical4Prop has top-left-bottom-right order.

As far as I understand validateRuleWithProps ensures that we always get 4 declarations so no need to check values length for less than 4 elements.

The declaration value shortening is fixed to work with top-right-bottom-left order so the shortening can proceed as:

# top right bottom left => top right/left bottom
10px 20px 30px 20px => 10px 20px 30px
# top right/left bottom => top/bottom right/left
10px 20px 10px => 10px 20px
# top/bottom right/left => all
10px 10px => 10px

[sssats]

@romainmenke can you merge that PR?