Refactored run.getRunner
Refactored run.getRunner

This fix ensures that the correct caption is loaded/used when finding a runner. It also also short-circuits a file-system check if the runner is available and doesn't require a refresh.

Partially fixes https://github.com/c9/c9.ide.run/issues/7
danallan/c9.ide.run,c9/c9.ide.run