Change sortComparePriority contract

[tshemsedinov]

Now: sortComparePriority(<Array>, <string>, <string>)
Needed: sortComparePriority(<Array>)(<string>, <string>)
We use this function only in impress (loading config), now we are going to extract this functionality into separate package @metarhia/config so we may change it without large refactoring.

[Bob-chemist]

@tshemsedinov, my PR:
Change sortComparePriority contract #319