Continueing compile fix.
Can't use static PAPI library anymore.

Conflicts with linking a Bro plugin.
Fixing nullptr dereference in some error cases.
Portability fix in script.
Turns out "\xXX" with printf isn't portable across shells.
Removing dependency on lockfile.
Adding Dockerfile.

This builds an image with HILTI compiled in /opt/hilti, Bro in
/opt/bro, and PATH setup to include both the HILTI toolchain and Bro.