Update CONTRIBUTING.md

Took out broken link to waffle.io; took out promise of a job interview with James, and minor copy edits.

CONTRIBUTING.md

@@ -1,7 +1,7 @@
 Contributing
 ============
 
-Want to contribute, but not sure where to start? Check out our [issue board](https://waffle.io/storj/core)! 
+Want to contribute? Read on! 
 
 Contributor License Agreement
 -----------------------------
@@ -12,17 +12,16 @@ You also assert that you have completed the [Contributor License Agreement](http
 Pull Requests for Swag
 ----------------------
 We love pull requests, so to encourage more of them we are offering
-awesome swag. Only SIGNIFICANT pull requests count. Fixing a comma
+awesome swag. Only significant pull requests count. Fixing a comma
 doesn’t count, but fixing a bug, adding more test coverage, or writing
-guides & documentation does.
+guides and documentation does.
 
 - Make 1x pull requests to get into the contributors list and website
-- Make 2x pull requests, we will send you a packet of stickers
-- Make 5x pull requests, and we will send you a t-shirt and more stickers
-- Make 10x pull requests, and you get a job interview with James + other swag
+- Make 2x pull requests and we will send you a packet of stickers
+- Make 5x pull requests and we will send you a t-shirt and more stickers
+- Make 10x pull requests, and you'll get a job interview + other swag
 
-If we miss a milestones (probably because we are working hard), just let
-us know so we can get you your swag. 
+If we miss a milestone, just let us know so we can get you your swag. 
 
 Style Guide
 -----------