Bump version.
updated packages.json
Bugfix.
More robustness for deepcloning.
Extracted Fragmenter from Document.Annotator.

This class is in general helpful for creating valid hierarchically
structured data (such as XML) in presence of overlapping
elements.
Extracted async methods into its own file.
async: iterated functions can also be synchronous.
Add Fragmenter.onExit.

This is useful to keep track of the current level.
Create slug utility function.
More sophisticated SubstanceError implementation.

As we proceeded our JS skills had grown...
Now the SubstanceError is capable of error chaining as we know it
from all other programming languages.
This is useful to wrap a low-level into a higher-level error.