Merge pull request #7 from colincross/contributing

Add CONTRIBUTING.md file
diff --git a/README.md b/README.md
index cf0f16c..45daed2 100644
--- a/README.md
+++ b/README.md
@@ -5,7 +5,7 @@
 modules that need to be built, and produces a Ninja
 (http://martine.github.io/ninja/) manifest describing the commands that need to
 be run and their dependencies.  Where most build systems use built-in rules or
-a domain-specific langauge to describe the logic for converting module
+a domain-specific language to describe the logic for converting module
 descriptions to build rules, Blueprint delegates this to per-project build
 logic written in Go.  For large, heterogenous projects this allows the inherent
 complexity of the build logic to be maintained in a high-level language, while
diff --git a/doc.go b/doc.go
index 23968cb..a3696b7 100644
--- a/doc.go
+++ b/doc.go
@@ -16,7 +16,7 @@
 // modules that need to be built, and produces a Ninja
 // (http://martine.github.io/ninja/) manifest describing the commands that need
 // to be run and their dependencies.  Where most build systems use built-in
-// rules or a domain-specific langauge to describe the logic how modules are
+// rules or a domain-specific language to describe the logic how modules are
 // converted to build rules, Blueprint delegates this to per-project build logic
 // written in Go.  For large, heterogenous projects this allows the inherent
 // complexity of the build logic to be maintained in a high-level language,