[BUGFIX] Pass ext_emconf.php errors

Make sure to show the specific errors why parsing the
ext_emconf.php has failed.

Resolves: #69741
Releases: master
Change-Id: I2fb1d4e85e5559c6248f3ada8a4e3c18098e12c4
Reviewed-on: http://review.typo3.org/43253


Reviewed-by: Jigal van Hemert <jigal.van.hemert@typo3.org>
Tested-by: Jigal van Hemert <jigal.van.hemert@typo3.org>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>