add notes on contributing

CONTRIBUTING.md

@@ -0,0 +1,10 @@
+How to contribute
+=================
+
+Contribution should be done in a separate branch. You can run tests as described in the [README](https://github.com/geo-frontend/nlmaps#developing).
+
+
+All branches that get pushed to github.com/geo-frontend/nlmaps also have tests run on CircleCI. When tests pass, create a pull request to the `develop` branch.
+
+
+Pull requests merged to `develop` are automatically tested and then merged into master, tagged, and released on Github (see [releases](https://github.com/geo-frontend/nlmaps/releases)) and [npm](https://npmjs.com/package/@geo-frontend/nlmaps).

README.md

@@ -413,6 +413,8 @@ For aerial imagery:
 
 ## Developing
 
+See also [CONTRIBUTING](contributing.md)
+
 ### Installation/set up
 
 To develop `nlmaps`, clone the repository and then in the directory run:
@@ -463,9 +465,11 @@ You can use the wrapper `serve-dev` to run the whole development setup, but note
 
 This publishes to npm as well as creates new git tags for the releases, which are pushed to Github. To finish the release, go to the  Github repo's release page and annotate the latest release for the 'nlmaps' package (this makes it show up under the 'latest' path on Github).
 
+**Note:** publishing usually happens automatically via CircleCI.
+
 ### Building the webpage
 To build the webpage goto the docs folder and make sure you have gulp installed. 
 
 Run `gulp build` to start the build process. When the process is finished the compiled website and assets are available in the build folder.
 
-**Notes:** the gulp build process copies nlmaps css and assets directly from `../packages/assets`.
+**Note:** the gulp build process copies nlmaps css and assets directly from `../packages/assets`.