feat(mdtest run/auto): support specifying multiple test scripts in the
test spec file and add --coverage option for mdtest to report code

mdtest now supports the execution of multiple test scripts.  This
feature can be used if running multiple test scripts only requires an
application to be started once before the first execution.  Subsequent
tests will not cause the application restart.

Code coverage support is also added in mdtest for both 'run' and 'auto'
commands.  mdtest is able to read code coverage hitmap from the
application after test execution and create a coverage info file in lcov
format so that coverage report tools like lcov/genhtml can be used to
create coverage report for the application.

Change-Id: I85cdb4df5112f7edb62397f552342b245c37d0c2
10 files changed