Tests assert that stderr contains no ERROR: lines after a successful exit
Rewrote sqlite_exec_int64() to separate error outcomes from legitimate
result values
Changed several WHY() calls to DEBUG()
Improved test framework
Improve regular expressions for common data types in test scripts
Revert column count field delimiter in "rhizome list" from ":" to "\n"
Add a few more test cases
- 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
