Update README.md

Fix typos

Author: mikela

README.md

@@ -2,9 +2,9 @@
 
 ------------------------
 
-##How it works?
+##How it works
 
-"Scala Exercises" brings the popular [Scala Koans](http://www.scalakoans.org/) to the web. Offering hundreds of solveable exercises organized into 42 categories covering the basics of the Scala language.
+"Scala Exercises" brings the popular [Scala Koans](http://www.scalakoans.org/) to the web. Offering hundreds of solvable exercises organized into 42 categories covering the basics of the Scala language.
 
 - LEARN: Each category includes an explanation of the basics. Learn the concepts through simple code samples.
 
@@ -15,7 +15,7 @@
 - EDIT: After completing a category, you'll be able to go back and edit it. Add new exercises or improve existing ones by sending a pull-request.
 
 
-##How build and deploy the app
+##How to build and deploy the app
 
 ```bash
 source deployIt.sh