Over the years PclZip became a maintenance problem. It's code base
is old and the official project seems to have died out. ZipArchive
is now more commonly available and offer an easier and more complete
API. So PclZip was dropped in order to focus our efforts on what matters.
Closes#18
Third party PDF libraries must now be installed via composer and naturally
via composer autoloading mechanism. Because of that it is not necessary
to specify their path on disk. The usage is simplified and it allows us
to include them in our unit tests.
This also means that from now on PhpSpreadsheet must use composer autoloader
mechanism. The internal autoloading implementation was dropped.
Adrien Crivelli