BenchExec 0.3

Most important changes:

• HTML tables now have header with direct access to plots.
• Maximum score of table is generated again.
• table-generator can now extract statistic values for other tools, too (not only CPAchecker).
• More flexible time limit specifications.
• Warnings shown if system swaps or throttles during benchmarking.
• Improved reliability of benchmarking: forbid swapping, use freezer to kill processes atomically.
• Renamed <sourcefiles> tag to <tasks> in benchexec input.
• Bug fixes.
• Added documentation.
• Added more tests.