install bashfoo lib in $datadir/bashfoo
bashfoo: when invoked with file as first argument just execute this script in bashfoo env
introspection: add list_functions
run.sh: fix quiet_if_success
* make check added; runs ./check.sh
* check.sh run automatic test suite
* test.sh - bashfoo auto test suite library
* assert.sh - assertion library
* introspection_test.sh, timeout_test.sh - new tests