Complete remaining TODOs in unit test script

Updated docker image unit test script, fixing the following TODOs:
- Replace os.system calls with subprocess.check_call
- Support possible configure.ac line breaks ('\')
- Updated 'make check' call fails Jenkins

Also added helpful command prints for Jenkins console

Change-Id: I6ba3986165b8d313228bcaa611df17bd213447eb
Signed-off-by: Matthew Barth <msbarth@us.ibm.com>
2 files changed