replace possessive with plural

Author: performantdata

_sips/sips/2014-06-27-42.type.md

@@ -207,7 +207,7 @@ val book: Book =
 
 shapeless enables generic programming and type class derivation by providing a mechanism for mapping
 a value of a standard Scala algebraic data type onto a sum of products representation type,
-essentially nested labelled `Either`'s of the records discussed above. Techniques of this sort are
+essentially nested labelled `Either`s of the records discussed above. Techniques of this sort are
 widely used, and removing the incidental complexity that comes with encoding via macros will improve
 the experience for many users across a wide variety of domains.