Fix #4460: Add Wiki documentation for adding the spotlight experience to any element

[JishnuGoyal]

Explanation

Fixes #4460
This PR adds a new page to the Wiki explaining how Spotlights should be used, how new ones should be added and how should they be tested.

Essential Checklist

• The PR title and explanation each start with "Fix #bugnum: " (If this PR fixes part of an issue, prefix the title with "Fix part of #bugnum: ...".)
• Any changes to scripts/assets files have their rationale included in the PR explanation.
• The PR follows the style guide.
• The PR does not contain any unnecessary code changes from Android Studio (reference).
• The PR is made from a branch that's not called "develop" and is up-to-date with "develop".
• The PR is assigned to the appropriate reviewers (reference).

[JishnuGoyal]

Additionally, here is this link to the original Spotlight Wiki doc: https://docs.google.com/document/d/1houcOoZLbTgdwnL1HnmocolEjP6exfY-R_qsNbYPY7Y/edit#

[BenHenning]

Thanks @JishnuGoyal! I think the filename is incorrect. Also we need to add this to the _Sidebar.md file so that it can be found on the side.

Besides that, since I've already reviewed the contents of this file in detail, I'm actually going to defer to @seanlip for the PR review since he's also broadly going to be reviewing wiki pages moving forward.

[BenHenning]

@JishnuGoyal please assign to @seanlip once the comments above are addressed.

[JishnuGoyal]

Hey @BenHenning, how exactly should I make sure this file is shown in the sidebar?

[JishnuGoyal]

PTAL @seanlip , thanks!

[seanlip]

Thanks @JishnuGoyal! Took a full pass, PTAL.

Re including this page in the sidebar, @BenHenning's already given you a pointer -- please add it to the relevant place in _Sidebar.md. Thanks!

[JishnuGoyal]

Please take another pass at this @seanlip , thanks!

[seanlip]

Thanks @JishnuGoyal, I think the page content looks fine. But I think you missed @BenHenning's comment from before. Could you please:

(a) Add this page to the _Sidebar.md file so that users can get to it
(b) Make sure this page is named in the same way as others in the wiki (no spaces in the name, use hyphens)

Once you've done that, this PR can be merged. Thanks!

[JishnuGoyal]

Updated the file name and added the same to the sidebar.

@seanlip PTAL, thanks!

[oppiabot]

Unassigning @JishnuGoyal since a re-review was requested. @JishnuGoyal, please make sure you have addressed all review comments. Thanks!

[seanlip]

Thanks! LGTM.

[oppiabot]

Unassigning @seanlip since they have already approved the PR.

[JishnuGoyal]

I have updated this branch. @BenHenning PTAL, thanks!

[oppiabot]

Unassigning @JishnuGoyal since a re-review was requested. @JishnuGoyal, please make sure you have addressed all review comments. Thanks!

[seanlip]

Merged. Thanks @JishnuGoyal!