typo fix

Author: aturon

_posts/2018-03-12-roadmap.md

@@ -72,7 +72,7 @@ form the backbone of the release:
   via “non-lexical lifetimes”, improved pattern matching integration, and more.
 - **Trait system improvements**, including the long-awaited `impl Trait` syntax
   for dealing with types abstractly.
-- **Module system improvements**, focused on increasingly clarity and reducing
+- **Module system improvements**, focused on increasing clarity and reducing
   complexity.
 - **Generators/async/await:** work is rapidly progressing on first-class async
   programming support.