Generate coverage information.
* autogen.sh: add options --coverage and --report to help w/ coverage info collection and reporting. * m4/gcov.m4: new file. Boilerplate for locating gcov et.al. * Makefile.am: add coverage-report target
To measure test coverage gcov and lcov needs to be installed and
./configure called w/ --enable-gcov. The coverage-html make target will
then create a HTML report.