Remove $FreeBSD$: one-line sh pattern

Remove /^\s*#[#!]?\s*\$FreeBSD\$.*$\n/

dwatch(1): Expose process for ip/tcp/udp

Knowing the value of execname during these probes is of some value even
if it is commonly the interrupt kernel thread (intr[12]) -- quite often
it is not, but that depends on the probe.

Sponsored by: Smule, Inc.

dwatch(1): Allow `-E code' to override profile EVENT_DETAILS

This allows quick changes to the formatted output of a profile.

Sponsored by: Smule, Inc.

Introduce dwatch(1) as a tool for making DTrace more useful

Reviewed by: markj, gnn, bdrewery (earlier version)
Relnotes: yes
Sponsored by: Smule, Inc.
Differential Revision: https://reviews.freebsd.org/D10006