readme: api wording tweaks
readme: api wording tweaks

thomaspark/bootswatch,nicolasmccurdy/bootswatch,thomaspark/bootswatch,douglaskastle/bootswatch,nkraft/bootswatch,nkraft/bootswatch,douglaskastle/bootswatch,nicolasmccurdy/bootswatch,nkraft/bootswatch,thomaspark/bootswatch,douglaskastle/bootswatch,nicolasmccurdy/bootswatch,iynaix/cointip_bootswatch,douglaskastle/bootswatch,iynaix/cointip_bootswatch,iynaix/cointip_bootswatch