main: Make ostree --version output YAML (and add gitrev)

I learned today that `docker version` does this and I really like
the idea.  While we have the patient open, also add the gitrev
with code taken from https://github.com/projectatomic/rpm-ostree/pull/584

Closes: #691
Approved by: giuseppe

tests/basic-test.sh

@@ -19,7 +19,11 @@
 
 set -euo pipefail
 
-echo "1..61"
+echo "1..62"
+
+$CMD_PREFIX ostree --version > version.yaml
+python -c 'import yaml; yaml.safe_load(open("version.yaml"))'
+echo "ok yaml version"
 
 $OSTREE checkout test2 checkout-test2
 echo "ok checkout"

tests/ci-install.sh

@@ -110,6 +110,7 @@ case "$ci_distro" in
             libcurl4-openssl-dev \
             procps \
             zlib1g-dev \
+            python-yaml \
             ${NULL}
 
         if [ "$ci_in_docker" = yes ]; then

tests/libtest.sh

@@ -538,7 +538,10 @@ skip_without_fuse () {
 }
 
 has_gpgme () {
-    ${CMD_PREFIX} ostree --version | grep -q -e '\+gpgme'
+    ${CMD_PREFIX} ostree --version > version.txt
+    assert_file_has_content version.txt '- gpgme'
+    rm -f version.txt
+    true
 }
 
 libtest_cleanup_gpg () {

tests/test-libarchive.sh

@@ -19,7 +19,7 @@
 
 set -euo pipefail
 
-if ! ostree --version | grep -q -e '\+libarchive'; then
+if ! ostree --version | grep -q -e '- libarchive'; then
     echo "1..0 #SKIP no libarchive support compiled in"
     exit 0
 fi