Addon treeFor method now uses an absolute path for the treeGenerator.
This is necessary to enable the consumption of torii by another addon.

Before already worked:
myapp ==requires==> torii

Now also works correctly:
myapp ==requires==> some-addon ==requires==> torii
Merge pull request #94 from manuelmitasch/enable-consumption-by-addon

Addon treeFor method now uses an absolute path for the treeGenerator.