Add more comprehensive examples

[danielocfb]

Tejun Heo authored the following program using BCC's Python bindings: https://gist.github.com/danielocfb/a294ed6125ac2140d36cad2b6f67a8af. It would be good to convert that to Rust & libbpf-rs and add it as another more comprehensive example. Feel free to grab this issue if you are interested in doing the conversion. For stack symbolization, the recommendation would be to use blazesym.