### changes
#### remove trailing spaces
When I was using example I noticed trailing spaces.
So, this PR removes the trailing spaces of json file, README, and others.
`examples/with-jest-typescript/src/modules/cars/Overview.tsx` also has it, but this time it did not change as tslint error occurs at commit.
I wrote a [script](https://github.com/j0lv3r4/dependency-version-updater) to update dependencies recursively in `package.json` files, e.g.:
```
$ node index.js --path="./examples" --dependencies="react=^16.7.0,react-dom=^16.7.0"
```
This PR contains the result against the examples folder.
Google seems to be deprecated the legacy realtime database and moving towards default use of Firestore, although it's still officially in beta. This PR migrates towards Firestore and the recommended loading methods for the Firebase 5.6.0 libraries. Note: the Firebase and Firebase-Admin dependencies should be updated to 5.6.0 and 6.3.0 respectively.
- The with-firebase-auth example won't run unless a database with proper rules is created first.
- Add a small error callback to addDbListener to help with debugging if someone's database connection doesn't work.
* Examples: clarify language around Yarn create & npx
* add missing READMEs and create-next-app usage
* suggest people tag jthegedus in firebase related issues
* add yarn alt instructions
* cerebraljs example readme & fixes
* remove global npm install of create-next-app
* add npx to create-next-app command in examples
* add bash to shell snippets
* add yarn create to next-app command in examples
* fix READMEs named with lowercase
* change READMEs to use UPPERCASE
getToken is now deprecated, you'll get the following message if using the previous code:
firebase.User.prototype.getToken is deprecated. Please use firebase.User.prototype.getIdToken instead.
* don't fetch messages server-side if user is not found
Currently, the component always fetch everything under '/messages' even if the user is not authenticated on the server side. Update it to not fetch if the user is not found as a better example on handling.
* fix lint error
* Rename Firebase Auth example
* Update gitignore to include npm5 lockfile
* Cloud Function
* Add Next app with two pages to demonstrate navigation
* Add Firebase Hosting and configuration to Host & Deploy
* Fix errors in rename for firebase-auth example
* Recommend pkg managers with caches for better perf
* Update with-firebase-hosting example
Fix code
* Update with-firebase-hosting example
Fix npm scripts and package.json files
* Update with-firebase-hosting example
Update README & install scripts
* Update with-firebase-hosting example
Update example package name
* Update with-firebase-hosting example
Fix to use single-quotes
* Update with-firebase-hosting example
VSCode did not like single-quotes! Sorry
* Fix gitignore file
