submodule
Merge branch 'develop' of https://github.com/readium/readium-js into develop
Removed the crypto library from the repo because it does not seem to be used
Resource cache size evict threshold improvements

* make the threshold configurable using a new Readium option
* in the absence of configuration option, try to determine the value
 based on browser's heap statistics before falling back to the default
 value of 100 MB.
Remove the implemented TODO comment.
Merge pull request #80 from readium/feature/resource-cache-configuration

Feature/resource cache configuration