iPXE appears to have *really* poor performance (orders of magnitude worse) if
it doesn't know the length of the kernel/initrds that it's downloading. Without
this change, booting CoreOS takes longer than I've had patience to wait. With
this change, the bottleneck becomes the network transfer speed.
Fixes#10.
pixiecore: Plumb NewSnooperConn into Server as an advanced option.
pixiecore/cli: Plumb DHCPNoBind to the CLI.
Now, by default, Pixiecore will bind() to the DHCP server port in a way
that shows up in `netstat` by default. If you want to enable the "coexist
with my existing DHCP server" mode, you need to explicitly pass
--dhcp-no-bind.
The main difficulty in passing a commandline as a plain string is
that you sometimes want to encode IDs into it, to tell your kernel
to fetch something via Pixiecore. Solving that problem with maps is
a bit clunky. Instead, now we use a text/template {{ ID "foo" }} to
mean "make a URL that, when fetched, reads the file "foo" from the
Booter.
Also introduces a "Trace" member to the API, for the future addition of
extremely verbose and complete tracing, to be used for bug reports. But
for now, only Log is used.
This version is still *extremely* barebones, and the unstable tag
in the README applies triple for it, but the code in its current
state is capable of booting x86 and UEFI clients correctly, and
that was hard enough to merit a snapshot checkpoint.
