coverage.sh: Added a helper script to generate HTML coverage reports.
coverage.sh: Added a helper script to generate HTML coverage reports.

The script uses lcov and creates a clean copy of the source code in a
temporary directory using 'make dist'.

sysdb/sysdb,tokkee/sysdb,sysdb/sysdb,sysdb/sysdb,tokkee/sysdb,tokkee/sysdb