|Task to import another build file into the current project.
It must be 'top level'. On execution it will read another Ant file
into the same Project.
Important: we have not finalized how relative file references
will be resolved in deep/complex build hierarchies - such as what happens
when an imported file imports another file. Use absolute references for
enhanced build file stability, especially in the imported files.
Import targets from a file in a parent directory.
Import the project defined by the property