Print kernel version, etc in GitLab CI (#147)

Print the kernel version and supported file systems inside the GNOME
GitLab CI jobs as a debugging aid.  Kernel version helps identify the
CI job runner's distribution to identify kernel features.  Supported
file systems identifies which ones can be mounted, should that be
possible in future.  Print supported file systems before and after the
tests because checking for support may load additional modules.  See
calls to Utils::kernel_supports_fs() for: btrfs, jfs, nilfs2 and xfs.

Closes #147 - GitLab CI test failure from *.CreateAndGrow/jfs

.gitlab-ci.yml

@@ -17,6 +17,7 @@ stages:
                      mtools hfsplus-tools util-linux cryptsetup device-mapper
                      lvm2 ntfsprogs udftools xfsprogs xfsdump
                      xorg-x11-server-Xvfb kmod
+    - cat /proc/version
     - cat /etc/os-release
     - systemd-machine-id-setup
 
@@ -34,6 +35,7 @@ stages:
                          hfsutils hfsprogs jfsutils util-linux cryptsetup-bin
                          dmsetup lvm2 nilfs-tools ntfs-3g reiser4progs
                          reiserfsprogs udftools xfsprogs xfsdump xvfb kmod
+    - cat /proc/version
     - cat /etc/os-release
 
 .build_stage_template: &build_stage_definition
@@ -86,10 +88,12 @@ stages:
     - GTEST_FILTER+=':My/SupportedFileSystemsTest.CreateAndShrink/btrfs'
     - GTEST_FILTER+=':My/SupportedFileSystemsTest.CreateAndShrink/lvm2pv'
     - GTEST_FILTER+=':My/SupportedFileSystemsTest.CreateAndShrink/nilfs2'
+    - fgrep -v nodev /proc/filesystems | sort
     # Create needed /dev entries for unit tests in Docker images.
     - tests/makedev.sh
     - make check
     - make distcheck
+    - fgrep -v nodev /proc/filesystems | sort
   # Save all files on job failure for investigation.
   artifacts:
     when: on_failure