Added support for reading epub files directly from a java.zip.ZipFile instead of a ZipInputStream:
the ZipInputStream approach stops reading from the input when a null entry is found, which in some cases leads to a toc-not-found-error.
Add sbt build file to project
Complete sbt project file
Merge branch 'master' of https://github.com/maylencita/epublib into maylencita-master

Conflicts:
	epublib-core/src/main/java/nl/siegmann/epublib/domain/Resource.java