gitignore: ensure .log and .junit.xml are ignored

Signed-off-by: George K. Thiruvathukal <gkt@cs.luc.edu>
tests: ensure run-examples.sh returns a proper error code when tests fail

Signed-off-by: George K. Thiruvathukal <gkt@cs.luc.edu>
tests: ensure run-application-tests.sh returns a proper error code when tests fail

Signed-off-by: George K. Thiruvathukal <gkt@cs.luc.edu>
biosal: update Makefile to clean *.log and *.junit.xml products

Signed-off-by: George K. Thiruvathukal <gkt@cs.luc.edu>