fix type in .init description

http://mantis.tokeek.de/view.php?id=430

defaults/yacy.init

@@ -1010,7 +1010,7 @@ search.ranking.solr.collection.boostfields.tmpa.1=text_t^1.0
 search.ranking.solr.collection.filterquery.tmpa.1=
 search.ranking.solr.collection.boostquery.tmpa.1=crawldepth_i:0^0.8 crawldepth_i:1^0.4
 search.ranking.solr.collection.boostfunction.tmpb.1=recip(ms(NOW,last_modified),3.16e-11,1,1)
-search.ranking.solr.collection.boostname.tmpa.2=Intranet Profile: when a search is done on a singe domain only, i.e. if a site:-operator is used
+search.ranking.solr.collection.boostname.tmpa.2=Intranet Profile: when a search is done on a single domain only, i.e. if a site:-operator is used
 search.ranking.solr.collection.boostfields.tmpa.2=url_paths_sxt^3.0,synonyms_sxt^0.5,title^5.0,text_t^1.0,h1_txt^5.0,url_file_name_tokens_t^4.0,h2_txt^3.0,h3_txt^2.0
 search.ranking.solr.collection.filterquery.tmpa.2=
 search.ranking.solr.collection.boostquery.tmpa.2=fuzzy_signature_unique_b:true^10.0