Make "path" a dev dependency.

Closes #18

R=rnystrom@google.com

Review URL: https://codereview.chromium.org//1605933003 .
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 21fbf36..bb4d88e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 2.1.8
+
+* Remove the dependency on `path`, since we don't actually import it.
+
 ## 2.1.7
 
 * Fix more strong mode warnings.
diff --git a/pubspec.yaml b/pubspec.yaml
index 46b7475..ad89309 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,15 +1,15 @@
 name: yaml
-version: 2.1.7
+version: 2.1.8
 author: "Dart Team <misc@dartlang.org>"
 homepage: https://github.com/dart-lang/yaml
 description: A parser for YAML.
 dependencies:
   charcode: "^1.1.0"
   collection: ">=1.1.0 <2.0.0"
-  path: ">=1.2.0 <2.0.0"
   string_scanner: "^0.1.4"
   source_span: ">=1.0.0 <2.0.0"
 dev_dependencies:
+  path: ">=1.2.0 <2.0.0"
   test: ">=0.12.0 <0.13.0"
 environment:
   sdk: '>=1.12.0 <2.0.0'