Merge branch 'bpftool'

Jakub Kicinski says:

====================
tools: add bpftool

This set adds bpftool to the tools/ directory.  The first
patch renames tools/net to tools/bpf, the second one adds
the new code, while the third adds simple documentation.

v4:
 - rename docs *.txt -> *.rst (Jesper).
v3:
 - address Alexei's comments about output and docs.
v2:
 - report names, map ids, load time, uid;
 - add docs/man pages;
 - general cleanups & fixes.
====================

Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>