Improved: Sorl external logging is not working, but a bit in console (OFBIZ-12646)

After removing useless system properties used to handle logging in
OFBizSolrContextFilter.java with commit 102eb511531d64c131ed78fe536fc2857b7eb4b1
that had a wrong commit title
<<Improved: Unable to upload a file through ecommerce (OFBIZ 12636)>>
and message that should have been:
<<Remove useless system properties used to handle logging. Maybe previously this
was working but it was then long ago.

Also speeds things a bit while loading Solr by using the not so obvious
SOLRHOME_ATTRIBUTE servlet attribute rather than the "solr/home" system property

Note: this is a 1st cleaning step and we are still missing external logging>>

I forgot to remove the related properties in solrconfig.properties, this does it
1 file changed