* Support for kernel up to 5.16
* bcc tools: update for trace.py, sslsniff.py, tcptop.py, hardirqs.py, etc.
* new libbpf tools: bashreadline
* allow specify wakeup_events for perf buffer
* support BPF_MAP_TYPE_{INODE, TASK}_STORAGE maps
* remove all deprecated libbpf function usage
* remove P4/B language support
* major test infra change, using github actions now
* doc update, bug fixes and other tools improvement