Log Message:
sysutils/bracket: import bracket-2.17

This is "bracket", a set of scripts for

 - Doing periodic builds of NetBSD-current
 - Testing the builds using anita (https://www.gson.org/netbsd/anita/)
 - Pinpointing regressions through automated binary search (aka bisection)
 - Reporting build and test failures by email
 - Generating HTML reports and graphs