Provide information on other profiling tools

At first it may appears to end users that the .cpuprofile format consumed by the extension may be the one documented here:
https://gperftools.github.io/gperftools/cpuprofile-fileformat.html

That would mean that it can be used to visualise profiles of native (non-js) applications generated with gperftools.

However, digging reveals details in the closed issue #1 revealing that the actual format used is:
https://chromedevtools.github.io/devtools-protocol/tot/Profiler/#type-Profile

It would be good to make this information more visible, by mentioning it in the extension description and / or repository's readme files.

It might also be useful to provide a link to documentation of the format that is used. It seems clear that there is going to be an appetite to use this extension for visualising profiles from other sources, and knowing the correct target format is the enabling piece of information for doing that.

A guide to any applicable conversion tools, or roadmap for supporting other input formats would probably be welcomed as well.

Review the extension description and repository README files, then compare their current wording with the DevTools Protocol Profile documentation linked in the issue. Update the documentation so the accepted .cpuprofile format and its reference are visible; any guidance on conversion tools or other formats should be scoped explicitly before calling the work done.