Enable parsing of @imports that are not on a new line

[jedfoster]

The app currently cannot parse this correctly:

$a:0;@import "SassyJSON";

(Per #85)

The algorithm that parses Sass input for @imports assumes that @import will be on a new line, not concatenated with other code.

[jedfoster]

This is an odd edge case that should never occur in the first place—we're using a pre-processor, FFS! White-space is our friend.