SECURITY.md for better vulnerability reporting

[roshankcjha]

Security guidelines for better reporting of vulnerabilities

Thanks for submitting a PR! Please read these instructions carefully:

• Explain the motivation for making this change.
• Provide a test plan demonstrating that the code is solid.
• Match the code formatting of the rest of the codebase.

Motivation (required)

Providing a documentation for reporting security based vulnerabilities.Fixes issue 613

Test Plan (required)

A good test plan has the exact commands you ran and their output, provides screenshots or videos if the pull request changes UI or updates the website. See What is a Test Plan? to learn more.

If you have added code that should be tested, add tests.

Next Steps

Sign the CLA, if you haven't already.

Small pull requests are much easier to review and more likely to get merged. Make sure the PR does only one thing, otherwise please split it.

Make sure all tests pass on Circle CI. PRs that break tests are unlikely to be merged.

For more info, see the "Pull Requests" section of our "Contributing" guidelines.

[roshankcjha]

Requesting @andrewimm and other maintainers of React-360 project to kindly look into this and provide the suggestions required for better templating.