* fixed one runCmd test: should be a valid command
+ added test for runCmd re-throwing exception; but disabled for now since domains are new in node 0.8 and buster isn't reliably working with them
* runCmd: now passes stdout and stderr to callback; arg opts now optional (!), using project.localPath if existent, dev-util.devDir otherwise
+ tests for dev-util.devDir and more for runCmd
* arg opts to dev-util.runCmd may also be null or undefined (equivalent to omitting it); + tests for that
* refactored tests
* refactored runCmd tests
* refactored runCmd tests again
+ buster-dev-tools.js: use custom wrapper around dev-util.runCmd to reduce redundancy in calls