FR: GitHub metadata - Releases

[GitMensch]

To do so: go to https://github.com/ostash/perfgrind/tags, then start with the 0.1 version on the right side "..." button -> create release

Then choose release title, suggestion "perfgrind 0.1 - initial release", with some release note, suggestion:

* `pgcollect` records samples for `PERF_COUNT_HW_CPU_CYCLES` events in userspace only at frequency 1000;  
both attaching to existing process and spawning new process are supported
* `pgreport` converts collected samples to 'callgrind' format;  
only callgraphs are supported; detail is always 'source file/line' (when debug information is available); instruction dumping is not implemented yet."

then the same for the 0.2 tag, suggestion "perfgrind 0.2" with

* new completely rewritten converter `pgconvert`, old `pgreport` is removed
* flat/callgraph profiles are supported
* different levels of details are supported: object, symbol, source
* instruction dumping is supported
* resulting 'callgrind' files are much smaller now, thanks to grouping hits by object/symbol/source file/source line
* `pginfo` utility for getting some stats about dump file.

and for now last one "perfgrind 0.3" with

* allow to set arbitrary frequency in `pgcollect` via `-F` argument
* handling of hits in PLT added
* properly handle page offset in mmap events

again for an example how this would look like:

https://github.com/GitMensch/perfgrind/releases and https://github.com/GitMensch/perfgrind (on the right)

For 0.4 you can then try "generate release news" button ;-)