Add summary output for memcheck.
Add summary output for memcheck.

MichaelClerx/libcellml,nickerso/libcellml,cellml/libcellml,hsorby/libcellml,libcellml/buildbot-testing,hsorby/libcellml,cellml/libcellml,nickerso/libcellml,nickerso/libcellml,hsorby/libcellml,hsorby/libcellml,nickerso/libcellml,MichaelClerx/libcellml,MichaelClerx/libcellml,cellml/libcellml,cellml/libcellml,libcellml/buildbot-testing