Add a new 'build-libsodium.sh' script and instructions in
doc/Development.md. Update the configure.in script to check for
libsodium headers and library, and print helpful messages if not
present.
The in-memory identity creation test was failing intermittently because
the server only creates the in-memory identity on the first tick, and
under load the server sometimes does not tick for a while, leading to a
race with the "servald id self" command.
The test case now waits for the server to emit a tick before running the
"id self" command. This necessitated a new DEBUG() statement and a new
debug flag 'overlaytick'.
Also disabled Rhizome for all the keyring tests, as unnecessary Rhizome
DB creation was slowing down the fixtures.
The quit-on-monitor-client-disconnect test was non-deterministic
depending on load (eg, other concurrently running tests). Under load,
it was likely that the server did not process the "monitor quit" command
before checking for disconnect, so the server did not terminate.
The fix was to make the monitor interface read and process all queued
input from the client before checking for HUP or ERR condition on the
socket. With this fix, the "sleep 1" kludges before and after the echo
"monitor quit" to the console command are no longer needed.
In the process the monitor interface code was modernised: eg, now it
calls read_nonblock() instead of read(2).
Already absorbs EINTR and EAGAIN. The monitor interface ignores this
error code for reasons unexplained, and now that it uses read_nonblock()
instead of read(), this preserves its behaviour.
./configure now fails if libsodium is not present.
Added libsodium to the list of dependencies in INSTALL.md.
Add a Debian apt-get command to doc/Development.md.
