Added `getLocationOnly()` to file system properties, to provide lazy access to just the location of the file system element, rather than both the location and the content of the file system element. This can be used when mapping the location of a task output to produce an input to some other task, without implying a dependency on the producing task. For example, an IDE project file generation task may need to know where some output will end up (so need to know its location) but does not use the content of the output.
Fix task dependency inference when a mapped task output file `Property` is used as input to an `@Input` on another task. Move some test utility methods out of the artifact transform tests into a more general place, and reuse in some of the task dependency inference tests.