Updated path to find zf2 library
Merge branch 'hotfix/epub-generation'

Fix epub generation
Merge pull request #791 from Spabby/hotfix/bootstrap-autoloading

Updated path to find zf2 library
[#791] Use either submodule or composer path

- Looks for submodule and/or composer path when trying to find ZF2
Merge branch 'hotfix/791' into develop

Forward port #791