Changed onload baselayer from greyscale to standard

[AnshitaVishwa]

Fixes #189 (<=== Add issue number here)

Make sure these boxes are checked before your pull request (PR) is ready to be reviewed and merged. Thanks!

• PR is descriptively titled 📑 and links the original issue above 🔗
• tests pass -- look for a green checkbox ✔️ a few minutes after opening your PR
• code is in uniquely-named feature branch and has no merge conflicts 📁
• screenshots/GIFs are attached 📎 in case of UI updation
• ask @publiclab/reviewers for help, in a comment below

We're happy to help you get this ready -- don't be afraid to ask for help, and don't be discouraged if your tests fail at first!

If tests do fail, click on the red X to learn why by reading the logs.

Please be sure you've reviewed our contribution guidelines at https://publiclab.org/contributing-to-public-lab-software

Thanks!

[welcome]

Thanks for opening this pull request! This space is protected by our Code of Conduct - and we're here to help.
Dangerbot will test out your code and reply in a bit with some pointers and requests.
There may be some errors, but don't worry! We'll work through them with you! 👍🎉😄
It would be great if you can tell us your Twitter handle so we can thank you properly?

[AnshitaVishwa]

@ananyaarun and @gauravano Kindly review it.

[ananyaarun]

Great work !! @AnshitaVishwa :)
I just changed the title to make it more descriptive.
Thanks!

[welcome]

Congrats on merging your first pull request! 🙌🎉⚡️
Your code will likely be published to https://publiclab.github.io/leaflet-environmental-layers/example/ in the next few days.
Do join our weekly check-in to share your this week goal and the awesome work you did 😃. Please find the link pinned in the issue section 📝
Now that you've completed this, you can help someone else take their first step!
Reach out to someone else working on theirs on Public Lab's code welcome page. Thanks!

Help others take their first step

Now that you've merged your first pull request, you're the perfect person to help someone else out with this challenging first step. 🙌

https://code.publiclab.org

Try looking at this list of `first-timers-only` issues, and see if someone else is waiting for feedback, or even stuck! 😕

People often get stuck at the same steps, so you might be able to help someone get unstuck, or help lead them to some documentation that'd help. Reach out and be encouraging and friendly! 😄 🎉

Read about how to help support another newcomer here, or find other ways to offer mutual support here.