Improved loader, TC support, and faster builds!

This is a pretty exciting release with some long overdue improvements. First off, better handling of relocations in the loader make writing idiomatic programs a lot easier, thanks to the work of @alessandrod. To make development faster, there's also an awesome patchset by @kbknapp that speeds up the build.

On top of that, the TC/libbpf compatibility improved in this release, so you can manually add multiple maps to the same ELF section using an improved API, thanks to @kbknapp. Improved examples are also added to the repo through the work of @rhdxmr

Contributors:
@alessandrod
@kbknapp
@rhdxmr
@shun159

Thanks to everyone who contributed to this release!
Happy hacking!