v2.0.7

• added support for containers with custom entrypoints by dumping the state of the environment upon launching the container to /.environment as a read-only file.
• added bug coverage command
• added is_alive to container manager
• fixed API regressions caused by transforming Container.bug from a Bug instance to a strspecifying the name of the bug.
• added len to FileLineSet
• added zero-argument constructor to FileLineSet
• added lines property to TestSuiteCoverage
• added files property to FileLineSet