chore: update CONTRIBUTING.md, bump node env (#68)

.travis.yml

@@ -1,7 +1,7 @@
 language: node_js
 
 node_js:
-  - 10
+  - 14
 
 branches:
   only:

CONTRIBUTING.md

@@ -1 +1,60 @@
 # CONTRIBUGING
+
+:tada::tada: First of all, THANK YOU for taking time to contribute this package! :tada::tada:
+
+## Steps to Contribute
+
+  1. please checkout [Issues Page](//github.com/liuderchi/ide-yaml/issues) and [Pull Request Page](//github.com/liuderchi/ide-yaml/pulls) first in case there is already someone being assigned or working on it.
+  2. fork this repo
+  3. clone the repo you just forked to your disk
+
+      ```shell
+      git clone https://github.com/my-account/ide-yaml.git
+      ```
+
+  4. install npm dependencies then *create a branch* named as the *feature you want to contribute*. For example:
+
+      ```shell
+      cd ide-yaml && yarn && git checkout -b refine-doc
+      ```
+
+  5. make changes to the code
+
+  6. you may preview your changes by [enabling DEV mode](#how-to-preview-your-changes-in-development)
+
+  7. you may test your changes. For example:
+
+      ```shell
+      npm run test
+      ```
+
+  8. commit the changes and push the branch you created to your remote
+
+      ```
+      git add ./
+      git commit -m "some changes"
+      git push -u origin MY_BRANCH
+      ```
+
+  9. [create a pull request](//help.github.com/articles/creating-a-pull-request/)
+
+
+## How to Preview Your Changes in Development?
+
+  1. uninstall `ide-yaml` if you have installed
+  2. change into the package directory you have forked and cloned
+  3. use `apm` command to link the package to atom user directory
+
+  ```shell
+  apm link
+  ```
+
+  Now your package directory has been linked to `~/.atom/packages/ide-yaml`
+
+  4. you can preview changes by launching (or reloading) Atom
+
+      - after your development, remove package link
+
+      ```shell
+      cd path/to/fork/repo && apm unlink
+      ```