- add assertGrep function
- improve --matches option for assertGrep and assertStdoutGrep: now
accepts [min]-[max] range, eg --matches=1-3, --matches=4-
- Put common utility functions into testdefs.sh
- Add abspath() and realpath() functions to test framework
- Test framework now executes all tests with working directory in a temporary
directory, to avoid pollution of caller's working directory
- Improve test log verbosity
- Name test log files by test script name