Refactored recursiveModuleCompile with promises.

Did some simplification of existing logic in recursiveModuleCompile, to
use promises more canonically.
Refactored recursiveModuleCompile with promises.

Did some simplification of existing logic in recursiveModuleCompile, to
use promises more canonically.

Finished last simplifications.
Fixed a final conflict.
Changed recursiveModuleCompile to use Promises.

Fixed some logic in recursiveModuleCompile.js to use Promises more
canonically.