The subscription changes in drum broke existing subscriptions. This
worked alright (though loud) for dojo, but it left chat-cli "frozen"
unless you manually unlinked/relinked. This does that automatically.
It also includes a refactoring of +on-load in drum, to avoid vain
repetition.
OTAs commonly end up in an inconsistent state if apps depend on changes
to /sys. For example, the %sift changes break on OTA because %spider
needs to be reloaded so that it's aware of the new thread type. This
adds a %goad app, which reloads all apps after every change to /sys.
Getting this to start OTA is nontrivial, but this pattern should work
for apps in the future. The changes to clock shouldn't generally be
necessary; they are only necessary here because we can't rely on hood to
start goad, since hood fails to compile if it's run before zuse is
reloaded. Once goad is active, this will cease to be a problem.
