[BUGFIX] Reload ext_emconf.php after extension update

If you overwrite an extension or download a new version with the
extension manager, the dependency check uses old ext_emconf dependencies
which are stored in the PackageManager. This patch extends the
PackageManager api to be able to create a new Package instance with
fresh ext_emconf information and replace the current instance. This new
function is called after an extension was extracted from a file or
was downloaded from the extension manager.

Resolves: #67367
Releases: master
Change-Id: I4d4dbb94aaafcbe1d99f496039d17d4856bce3bd
Reviewed-on: http://review.typo3.org/40935


Reviewed-by: Helmut Hummel <helmut.hummel@typo3.org>
Tested-by: Helmut Hummel <helmut.hummel@typo3.org>
Reviewed-by: Alexander Opitz <opitz.alexander@googlemail.com>
Tested-by: Alexander Opitz <opitz.alexander@googlemail.com>