Add line numbers to golang integration

I looked into this and it seems possible, the data is already in pprof: https://gist.github.com/petethepig/bc39271d0dd213db768e649274ab6edb

Long term we should rethink the way we store these, I made an issue #705

Short term, we should get the lines during the pprof parsing stage and add it to the string right after package name perhaps? We'll need to make sure we do a few more things after this:

* [ ] make sure regex that we're using on the frontend still works, or modify it if needed
* [ ] make sure pprof export works properly after we make this change
* [ ] think about how this affects grafana plugin, make changes if any changes would be needed