test: initial refactor to support running in parallel in an unshare

The release suite fails with no permissions to dump loopback, so let's
run tests in an unshare, one per test, with and start as many syslogd as
needed for each test -- also easier to debug since all are then fully
stand-alone.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

test/api.sh

@@ -1,9 +1,5 @@
 #!/bin/sh
-set -ex
-if [ x"${srcdir}" = x ]; then
-    srcdir=.
-fi
-. ${srcdir}/test.rc
+. ./start.sh
 
 export MSG="no-openlog-apitest"
 
@@ -42,3 +38,4 @@ echo "= Phase 4 - Verify RFC5424 API with logger(1) ==========="
 sleep 2
 grep "exampleSDID@32473" ${LOGV1} || (echo "== ${LOGV1}"; tail -10  ${LOGV1}; false)
 
+. ./stop.sh