migrate to SCL
pass filename to sed

addressing: sed: no input files
do not install files into /opt directory

and remove percent sign (typo) from sed expression
even subpackage should be without scl prefix
use non-scl paths on non-scl distribution
fixing user pass install not working

TempFiles are deleted at garbage collection time
http://www.ruby-doc.org/stdlib-1.9.3/libdoc/tempfile/rdoc/Tempfile.html

Previously we would simply return the path, discarding
the file object, so as soon as the create_temp_config_file
function returned, the file may be deleted.  Now we keep
track of the file object through the life of katello-configure

Just mimicing https://github.com/Katello/katello-installer/commit/a6c70c639c549283713d4f0e7f795ac560c0bf9c
remove percent sign (typo) from sed expression
Merge pull request #1 from xsuchy/pull-req-scl

migrate to SCL