build: add `.npmignore` to remove unneeded files from npm package
diff --git a/.npmignore b/.npmignore
new file mode 100644
index 0000000..d71cbd7
--- /dev/null
+++ b/.npmignore
@@ -0,0 +1,16 @@
+# CI service configurations
+.travis.yml
+.appveyor.yml
+appveyor.yml
+
+# Testing, code coverage, and linting
+.eslintignore
+.eslintrc.yml
+
+# Git
+.git
+.gitattributes
+.gitignore
+
+# Github
+.github